well, there are plenty of resources out there...but first, what is it that you would like to do? do you want to get bigger? stronger? are you training for a sport?
as far as stomach exercises with weights, try a weighted sit-up...just liek a regular crunch with a weight on your chest. if you do it on a decline bench, its even better. if you want to get bigger, 2 sites i recommend are hardgainer.com and bodybuilding.com...ive found lots of useful stuff there. if you want to get stronger without bulking up a whole lot, look up some powerlifting sites.
also, i would recommend doing your lower body in addition to your upper body. it will actually speed up development of yuor upper body.
well, try those sites...good luck!