Anti-theft tips:

Secure all of your receipts of ownership together with serial numbers and photos of unique aspects of your gear. A photograph or a serial number can be like a fingerprint. This is crucial. Without at least a serial number, photo or preferably both- you won’t come close to getting your gear back.  Make copies and keep them with you. When you’re 1000 miles from home you can make an immediate claim with the local police.

Don’t advertise your band on your van or trailer.  Traveling incognito is not as cool, but it saves big on security.

Get insurance from someone like http://www.musicproinsurance.com.  You’ll understand after the first time you get something ripped off.

Always leave someone with the gear! Duh, right?  But you really have to make an effort sometimes.  Sleeping with the gear can be tough but you need to find a solution when the need arises.  A buddy system is always the best.

Don’t be complacent.  If a location doesn’t feel right- move.  If you’re tempted to split for a minute, but the gear will be alone- stay.

Link to or list on as many sites as you can and remember to post on the TheGuitarSite.com’s Stolen Gear Registry.  The largest stolen gear hub on the web.

Links

http://stolengear.org
http://stolenguitarregistry.com
http://www.stratoblogster.com/2006/09/stolen-gear-resources-for-musicians.html
http://www.guitarsite.com/database/Guitars/rec/2995