If you want to go to Friendship, IN in July, the NMLRA hosts its national BP matches and there are rows upon rows of sutlers hawking anything from tanned leather to parts to assemble your own gun - including wood. Wood is something that you should pick out.
BTW, since this is your first time, don't spend too much money on fancy wood right now. Make your mistakes, ahem, learn on cheaper wood and when you're better, go with a higher grade wood then. Also try some of those pre-carved and pre-inletted stocks. Final fitting is left to you.