I have a smith&wesson 357 mag model 7, i can't find any info on it, where can i look?

If it's a newer numbered model revolver, there should be a model number with any revision number stamped on the frame. You can see it when you swing out the cylinder. It would be stamped on the frame where the cylinder pivots, in front of the cylinder below the barrel looking at the gun with the barrel pointing to your left. They began stamping the frame in 1958.