Here's my list of favs:
Editing: Soundforge
Multitrack Mixing: Nuendo
Soft Rack: Reason
CD Mastering: CD Architect
That'll cost you a bundle unless you have an eyepatch
Oh and theres this program called Acid. Loop based and very easy to use.. so I would suggest getting the music you wanna mash up.. extracting loops if possible and then 'painting' you mix. You'll see what I mean by painting when you try it out. Come to think of it.. depenRAB on what kind of music you wanna make?
