NAVHDA is good but they mainly cater to versatiles. Another good field trail association is NSTRA. They also have chapters all around the country.

What I would do in your situation is read a few good books and videos. Delmar Smith/Bill Tarant book would be a good start.

If you already seeing a professional trainer, follow his advice (if you trust him) but I can't see where not putting your dogs on birds would hurt. But give upland birds a try, it's a blast when you have a good dog.