Music theory...there's a whole bunch of books out there as well as the internet that you can study up on.

Collect music...locate lyrics/tabs/etc. of songs you want to learn. If you don't want to print 'em out on your trip, email the links to yourself.

Take a trip through Guitar Tricks...see what's available and what you'd like to tackle next. I always like to take a listen to new lessons before I actually sit down to start 'em.

Surf through the internet...there's tons of other (often free) lessons out there, other forums and blogs, and stores for toys. I discover ones new to me almost weekly.

Check out streaming radio stations and podcasts...sample new genres, find stations or podcasts playing music you'll never get to hear on 99.9% of terrestrial radio. (start with montanaradiocafe.org ;) )

Check out European TV...there's a bunch of music programming.

Hit the music stores...take a look at the guitars manufactured over there.

Drop in and say 'Howdy' to Justin ( Justinguitar.com ). :D