I learned from This Book years ago, it has some great instructions on canvases, wools, frames and the basic stitches (as well as some amazing patterns for all experience levels). There are only 3 stitches, basketweave, half cross stitch (tent stitch), and cross stitch.
It's seriously not much different from cross stitching, except you use canvas, and the setup into the frame can take an hour or so. Needlepoint rocks, you're taking the jump from 'frameable' art (cross stitch /embroidery) to hardwearing, durable works that can be used to make seat covers, cushions, upholstery, bags, ect that will last a lifetime. :D
[edit] it seems that in the US and UK 'needlepoint' can mean different things. Here in the UK it's done with wools on canvas. If it's thread/floss you're looking to use, /r/crossstich is good :)