Go with a lower end board from either Double Up, Liquid Force, Hyperlite or GB. Stay away from anything super agressive(sharp/cupped rails, large molded in fins...) Most of the entry level boards from these companies are old pro model boards, that will be able to take you through all the basic tricks. The more you ride, you'll start to realize what you like and what you want in a board. Then I'd suggust picking up a higher end board.
Also, I'd suggust that you find a reputable school in your area and get a one hour lesson. That way you can learn the right way, which will save you many painful falls and also help you learn new tricks faster. Bad habbits will take you twice as long to fix down the road.
Mike Schwenne
www.westcoastcamps.com