www.littlesounddj.com (same with nanoloop, you need a GAMEBOY EMULATOR to run this. The audio can then be recorded.)
www.8bc.com (not a direct link to a website but has loads of links on the forums)
www.anvilstudio.com (Windows program)
www.nanoloop.com (actually please dont buy this download it (semi-illegally) coz I hate the guy who wrote it. Such a tight-bum)
http://lmms.sourceforge.net/home.php (Linux program)
http://sourceforge.net/projects/modplug/ (Easy tracker-system program for Windows and Game a Gogo swears by it. Good also if you can't figure out LSDJ. LSDj is for more techie types.)
GAMEBOY EMULATOR:
http://vba.ngemu.com/If you need more programs just tell me.
I just have one question though...how the heck does someone who has only made one post, and that post is a question, get 24 points? Odd...but this is no flame, relax.