First of all, you're likely to get a warmer reception in our neighbor to the north- Canada. There you would have the advantage of still being part of the "family," as well as an opportunity to learn a code, and practices, quite similar to ours.
The major union here, for electricians, is the IBEW, or "Int'l Brotherhood of Electrical Workers." There is a very good chance that they have some sort of arrangement with your trade union- might as well ask!
Our job certifications are not national; the 'rules' for getting your Journeymans' Card vary from place to place. Chances are, simply providing documentation as to your work experience will get you into the test.
Mike Holt (
www.mikeholt.com ) has a selection of superb books that outline our practices, and a Masters' test that is far more thorough than any you'll ever really have to take. For someone in your position, his series "Understanding the NEC" is a good place to start.
