I was reading Ana's Girl's blog posts from June. (I'm behind on all your blogs!)
Some things she'd written reminded me of isometric exercises, and of at-home-no-equipment exercises. So here's some links.
Isometric Exercise tutorial
Shape's Workout links page
Bunch of info about muscle groups, simple exercises, callisthenics right HERE.
Just about every magazine geared towards women has a website with a fitness/exercise section.