Ableton Forum

I've seen a couple of tutorials on this, but want more extensive info on looping, say, a guitar in live performance on the fly.
I want to mess with the audio and feed the samples back to the band as we play.

Also to use as an independent compositional tool.

Any recommendations? (Ableton 8.2.1)

Sounds to me like you need to figure out more exactly what you want.
There are several different ways of working with real-time recorded loops, but I would start with the Looper.
Sends and returns are also very handy.