Really fruity loops is the easiest out there. It is very simplified compared to all the other softwares out there. You may be able to find cheap software but it will lack in functionality and quality. Ableton, FL, Reason (does anyone even use this anymore?) Logic, Pro Tools, or even acid would be pretty much the only programs that you can use fully. There are trackers too, but you would have to talk to Graph and Dword about those.