I use Digidesign ProTOOLS. Like Kung Fu said you simply want to mix music in Premier is all you need. If you want to chop songs up or add cool effects I like ProTools but there is a limmitless amount of digital editing software out there. If you are a student you can get the MBox(digidesigns hardware) and the program for about 400 bucks and the Mbox has middi, RCA, and XLR inputs for recording purposes.
http://www.digidesign.com