A couple of years ago when I really started quilting, I bought a free motion foot and a walking foot, for about $25 together, I think. I also recently bought a book called "Quilting in Sections" by Marti Mitchell. I consider these investments, since they help me save a lot on sending tops out to be quilted.
I taught myself to free-motion quilt and straight-line quilt. It's really not hard, I didn't take a class, just learned out of books and from trying stuff.
I haven't done a queen quilt yet (that's my next project, assembling & quilting a queen size sampler that I've got all the blocks for), but have made seven or eight baby to throw size quilts, and several wall hangings, from start to finish, so it's been well-worth it to me.
If you don't like to do a project just to learn on that you'll throw away, consider potholders. Manuevering a potholder is easier than a larger quilt, anyway, so it's a good place to start learning. Then maybe try a table topper or baby quilt (I like to use baby quilts to test out new techniques).
Also I did take a quilt class once and the teacher said she never used walking feet, just the regular presser feet. And she did very nice work. For myself, I think the walking foot makes a nicer end product, but you might give both a try to see what you think.