I just found a great article on how to make a home music studio on the cheap in the latest Popular Mechanics issue (February 2010). I've given a few hints and articles on getting started in synthesizer music, but a full fledged DIY article was in the works. When I read this article, however, I thought it did a great job for the beginner who wants to setup their home music studio. I'll make a rundown of what you need, but you'll need to get the article for the full details.
The main things you will need are a computer(Mac or Windows or even Linux), a good recording Mic, a drum board, a keyboard, and a good sound card on your computer. There are other things you can add, but I think this is a good start. Popular Mechanics goes into the details of the exact products you should get, and gets you a professional home recording studio for under $5000. You check out the article and my next few articles will help you get your pro studio for under $1000.

US $3.50