Replaced door hinges on front door and now the door has a gap on the lower portion along the front edge and fits fairly close as it goes up the door like it did before. So do I put the shims on that bottom hinge to move the door forward and close the gap?
Shims are normally installed between the jamb and the framing, not behind hinges. If you can't do that, you can shim hinges, but it'll make your hinges protrude and it'll increase the gap there, making your weather seal less effective.
It's also possible that you've simply run long screws int too far, pulling the jamb outward. If so, simply back them off a bit.
Your guess sounds right. The answer is "wherever they're needed to solve the problem".