I'm no expert, but I would suggest buying a tactics book first. Just about any book on tactics will do just fine. If you're like me, I would go for the cheapest I could find, lol.
chess book

Seriwan is a good choice
If you like Amazon, I suggest you have a quick look at Listmania. Lost of guud lists on Beginners books. However, start with a tactics book!

The Complete Idiot's Guide to Chess
Don't be put off by the name, it's a good book.
if you want just ONE really really good chess book, this is indeed the book:
http://www.amazon.com/Complete-Idiots-Guide-Chess/dp/0028617363

Once you have mastered the basics, a book I cannot recommend enough is "The Mammoth Book of Chess" by Graham Burgess. There is some "How to play chess" rules etc. plus delivering mate. But it also goes on to give you invaluable chapters on tactics, combinations, endgames, openings etc.
It has opened my eyes to the amazing tactical possibilities in chess. Highly recommended once you're beyond the idiot's guide phase ;)
im interested in buying a chess book, but have no idea which one to get. i dont know much about chess other than which pieces can move where, that is, i have no knowledge of tactics or openings or anything! so i want a basic book, something to get me started . . . .any ideas?