I didn't read the whole thing, but
this site seems to have information you might find useful. It's only a start, though. I'd suggest researching each state you intend to travel in, and even print out the applicable statutes and keep them with you (unrelated example: Colorado law allows you to drive a vehicle you purchased without a license plate if you purchase it after 4pm or on a weekend and you are driving it home from the purchase - I print out a copy of the law and bring it with me in case I get stopped by a cop who doesn't know that. They can't possibly remember EVERY law on the books....)
You may have to make the choice to not visit certain states, or to leave the gun at home. Just be sure you make either decision based on actual laws, not guesses, as the ramifications either way could be serious.