Do you get an error message if you plug in your guitar and then start gtkguitune or another of your guit progs via
terminal? Do you have qjackctl, jackd installed?
I believe in everything, except humans.
LM9, Debian Testing Xfce, Debian Sid Xfce - CPU/Amd64 2,6Ghz, Graphics/Nvidia 9600 GT, Sound/SB Audigy4 emu10K1