Ok... please dont take this as a snarky or rude comment, but in my time here I've seen too many people simply coming at Vodou from a totally wrong angle... and I hope I can help set it straight a little bit to help you get a real footing.
There's a really big split between Haitian Vodou and Louisiana Voodoo (these are the two spellings; the ones with an N at the end are just french versions; the D is NOT capitolized, got no clue what's up with that.) Louisiana Voodoo is primarily a magick system that uses spirit names and signs as symbols to throw power behind, and can be done on your own. (In fact, I think it's largely a solitary practice) It honestly has little to nothing in common with Haitian Vodou; a couple spirit names cross over, but mostly its concerned with the spirits of Santeria and Lukumi (Yemaya, Ochun, Babalu Aye... none of these spirits exist in haitian style work... so if your book mentions them and how to work with them, its not a book about Haitian Vodou.;)
The first order of business, seriously, is checking at your local botanicas (and doing the legwork to find where they are... citysearch.com and just type in botanica can get you a very, very long way). Botanicas are supply stores, usually for the Santeria community although in any area with a haitian presence usually they'll also cater to us and stock the things we need... but they're also usually run by practitioners. Asking if there's anyone who can give you a reading is an EXCELLENT way to make an introduction... and since readings are done by clergy, you have a clergy member in front of you to talk to.
Its more polite than saying "I need to talk to a priest, do you know any?
...and it puts a priest in front of you.
Generally, expect to pay somewhere between 30 and 50 dollars (here in the US, I dont know about other currencies in other countries); make sure if its something that interests you to ask what spirits you should be serving. This is CRUCIAL, ok? Simply tossing service around as though they're all going to listen to you and do what you say is DANGEROUS. This is not Wicca... names and spirits are NOT interchangeable (and other than the way Caminos work in lukumi related traditions, we DO NOT HAVE triple goddesses, aspects, or any of that stuff. If someone says they do THEY ARE LYING TO YOU.) You can serve the spirits you have around you at home, with the greatest of ease. Its not expensive, doesnt really require special tools... just things that once you give the spirits you never take back. Cheap dishes from a local salvation army store or its equivalent are fine for serving your spirits, just make sure they're a different pattern from the ones you use so you dont mix them by mistake.
Get a reading.
The reader will also be able to tell you if the spirits are calling you to work with them and if you are meant to initiate. Not everyone is... in fact its actually pretty rare that the lwa want you as one of their priests. You can still serve at home, most certainly... but you need to know this information. You need a face-to-face with clergy to tell you what to do, or frankly you're hosed.
Get a reading.
While you have the reading, you can ask your reader what tradition they come from and to tell you a little bit about it... ask if they know people from other related traditions who are in your area (IE if the wonam reading shells for you is a Santera, maybe she knows if there are Haitian practitioners in the area... MANY times we cross trads for readings, and many times we just like knowing that other similar but different trads are in our region)
If you want to learn more, PLEASE PLEASE PLEASE talk to your reader about it... you have them right in front of you and they can see in your reading that you want to work with the spirits. They are a better resource than ANY BOOK OR WEBSITE CAN EVER BE.
Know, though, that you can NEVER in any of these traditions, be a self-initiate or try to do the whole thing solely on your own. It cannot happen. Even Louisiana Voodoo requires initiation, and you need the people to initiate you to ever earn the title of Houngan or Mambo. (louisiana also just doesnt have what the other ATR's do... I'll be fully honest, we look down on it a little. Its not -bad- per se, its just horribly incomplete, mixes things in a really strange way, and doesnt build as close a connection to the spirits themselves as the other traditions of Vodou, Santeria, Umbanda, Candomble, Palo Mayombe, etc)
You WILL have a botanica or something similar in your nearest major metropolitan area. You will be surprised at just how far a reach these traditions really have... especially once you start being able to see how much is hidden in plain sight.
HOWEVER... if you strongly feel that there is ONE specific tradition you MUST work within that is not represented in your area, Im very sorry to say but you will have to move. There is no way to do this on your own if you want to be an initiate; we become our initiators family (I call my priestess Mama; I am her son jsut as though I were born to her, and her own children are my brothers and sisters now) If you want to progress as a priest or priestess, you WILL NEED TO BE NEARBY, or be wealthy enough to travel regularly.
One of my good friends here in Boston is an initiate of a house based out of NYC/Brooklyn. He has to travel to New York very very often; any time his Maman has a celebration or even information to teach (and you have NOOOOOOOO idea how much there is to learn! Its exciting!) he has to drive to new york... and he does so gladly.
There is no book that can accurately teach you.
Kenaz Filan's Haitian Vodou Handbook is pretty much the only how-to book there really is (Trust me on that one... Ive read a great many books and have a library of close to 2000 books in my bedroom alone; on the other side of initiating and becoming a houngan asogwe, I tell you with all honesty that the other books that pretend to be how-to books for beginners are trash. Trash. Not worth the paper they're printed on.)
Better are books like Maya Deren's Divine Horsemen; that book is astoundingly beautiful. Karen McCarthy Brown's Mama Lola.... my god, if you have ANY interest in Vodou you MUST read this book. Katherine Dunham's Island Possessed... good. very good. Not as good as the two I just mentioned, but still good.
That's honestly it for the books I think you need. 4 books. A quick library trip, and you can do inter-library loan if you need to. They will give you a pretty accurate picture of what Haitian Vodou is like... but all of that will dissappear into a sense of wonder the moment you set foot into a Vodou celebration or party for the spirits. Its amazing... and that feeling of getting the community together and singing for the lwa with their drumbeats and the sacred asson rattling... there are no words. It trancends spells and magic and asking how-to-do-what... its breathtaking. Its home.
As far as asking what to give who, and who likes what offering... honestly? Its different from house to house. Some things are the same, but most are a little different depending on lineage and what region the House is based in. I could tell you all about how my house serves our spirits, and in all honesty it will be useless information for you. The house you find will probably do things differently (within reason; the tradition DOES have very strong bases that resonate through all houses)
DO NOT FALL FOR ONLINE MAMBOS WHO SELL YOU INITIATIONS. There are a few people around who say they have huge international memberships and that you can just log on to a webpage, pay for your initiations, and off you go to haiti. NO NO AND NO. This is a faith about community, and you need the community around you. Its better to live close (Within an hour or two, preferably, so getting there is easy) to your home temple; the online society thing is bullshit. I warn you very, very, very strongly against those Houses who promise everything through a website and an online email forum or two... it can never compare to the real thing, which is tradition for a reason.
IF by any chance you're here in the New England region, we've got PLENTY of houses (my own included, and my Maman is a wonderfully loving, sweet, and whoppingly powerful mambo ;) and we'd love to talk to you.
If not, PLEASE PLEASE PLEASE do this FOR REAL; that means going to get a reading, and researching who you have in your area. Books arent going to cut it, and Im serious... if this is your passion, you need to live near it.
If this isnt your passion, please understand that dabbling is dangerous; our spirits are not jsut names, they are consciousnesses of amazing power but also dizzying and terrifying anger if they're not treated with respect. ONLY SOME OF THEM ARE FORGIVING OF BEGINNERS: there are a great many spirits who do not forgive a beginner as they'll just wonder what the hell you were doing calling to them if you didnt know how to handle them.... its not pretty.
Plus, our secrets are secret for a reason; during the initiation process there are vows that must be taken and promises that must be made to maintain the purity of the tradition and to teach it with respect. This is not an area where "ecclectic" is OK; this is not an area where information can or will ever be freely given.... initiation proves that you are worth teaching secrets to, and VERY VERY VERY bad things happen to those who break their vows. Again, this is not Wicca.... this is Vodou; this is a changing and ever evolving faith that has roots, provable and unbroken roots, to before the dawn of recorded time.
I wish you the highest in honor and respect along your journey; may it take you where you need to go.
Houngan Matt
Bozanfé Bon Oungan Daguimin Minfort