Have a look at The Cake Bible by Rose Levy Beranbaum and/or her website www.realbakingwithrose.com
if you want a strong foundation in understanding the ins and outs of baking. I can't say that her approach will be inexpensive, however, as many of her cakes require ingredients the average person doesn't have on hand. But there are definitely some good basic cake recipes she offers. Also try Martha Stewart's recipes; a lot of people are happy with her red velvet, for example. Again, Joy of Baking is a good resource too. It's a little hard to be super specific on an inexpensive recipe since everyone's idea of expensive vs. inexpensive can vary.