Hi...I'm getting ready to go on tour in Europe with my friends' band as guitar and drum tech, and was wondering if anyone had thoughts on what kind of basic gear I need to be sure to have with me to keep everything in working shape. I can do the basics, but have mostly just been doing weekend gigs with them for the last while, and in the US we could always find a store the next day if anything needed fixing.
Also, does anyone know of any kind of "guitar tech field manual" type book that might exist with basic repairs and advice, etc?
Thanks for any input anyone has.

Voltage is obviously different so get a really good converter kit because this is gonna power your soldering iron in a hotel room (strictly forbidden but you'll have to do it anyway) and in clubs when you need to fix busted input jacks etc.

Soldering iron, solder.
Allen wrenchs for bridge adjustments and truss rods.
Phillips head as well as flat head screwdrivers.
A good needle nose, wire cutters, etc.
A batterey powered screwgun is nice but not necessary.
Strings, 9v batteries, an extra strap or two, picks.
A couple of short cables for pedalboards.
Maybe some "george L's" cable and connectors (?)
A tuner.
Duct Tape.

There's probably plenty more things depending on the gear your band is taking over there but this list should get you thinking in the right direction. No "roadies intruction manual" that I know of. Have fun!

Here's a great book on guitar repair... a reference to have... mine paid itself in savings from repairs over the years... Guitar Player Repair Guide
Check the link out you can view a bit of the book on there... the book also adress basic tools to have handy etc.

Hope this helps...

Since you're doing drums too. Keep an extra drum key around your neck and have a few in your bag. Also the springs and or tensioning mechanisms for the bass drum pedal is good to have as they tend break and/or get lost in transit.

The guitar player repair book glorbz mentioned is really good. I forgot about that one.

great info guys, thanks! I had actually been looking at that book on Amazon with some others, but didn't know which to get, so I'll definately pick that up.