Hi,
There's a lot of good trumpet specific information over on Forum: trumpetherald.com
There is a forum dedicated to mouthpieces under the equipment heading.
I have been teaching myself trumpt for 8 months and would not have been able to do it without them. I am thinking about getting a new mouthpiece myself. I am still struggling with upper range. I don't know if it is too soon to tell if it is me or a mouthpiece issue. I am considering the Jerry Callet Superchops 2 MASTER SUPERCHOPS, if I can come up with the money. It may be worth saving up. $125 + s/h I'm not in any hurry though.
How high do you need to play with the big band stuff?