http://www.evergreengrowers.com/met5.../met52-ec.html
I haven't tried it on a squash bug problem, but I have really liked Met52 so far. I know it kills potato bugs, who were the collateral damage when I sprayed it for whiteflies. The stuff works like it is a nuclear option of pesticide, but it is harmless to people. It's pricey, but a little goes a long way.