Where do I get married in Baltimore, Md? I want like a courthouse something just between me and him

I would say at your county courthouse. You can give them a call and see what paperwork is required, etc.

For what its worth, my wife and I were married by a Justice of the Peace in Baltimore. This was in 1965 but I willing to bet there are still Justices alive and well even now.

You will still need a Maryland License to wed.