If you are using an mac protools plus an apogee duet would be the way to go. You can find used apogee duets around $300.
He has a II. No need for a Duet or any audio interface.
And Protools just for clips?
It wouldn't just be for clips. But given the price jump, I'll probably get the $60.00 program...and get my feet wet.
Definitely Reaper....
used most of the others out there at one point or another including various releases of Cubase, Nuendo, PT, Fruity Loops, Sonar, Wavelab, Magix, Ableton, Acid, BIAB, Audacity, Reason/Recycle and even SAW Studio (among others) - and plenty of freeware/shareware stuff too.
For price/value... nothing beats Reaper IMHO.