does anyone know how the prssure detonated mines work and any booby traps made from things around the house (and maybe some things that arn't)?

http://www.howstuffworks.com/landmine.htm

that should explain basics

You can make a quick and dirty landmine by removing the bulb from a taplight (you've seen the advertisements on TV, I'm sure) and affixing a model rocket igniter to an explosive charge. Bury it, and don't walk on that spot again. A simple cratermaker will make a lot of noise and throw some dirt, and a sachel of acetone peroxide will likely get someone airborne. ANFO, dynamite, or any other high order charge is icing on the cake.

These devices aren't waterproof, but you can easily fit one inside a large ziplock bag.

~Zero the Inestimable