I'll have more links here before too long. If you have any you'd like to see here, just email me.
http://trumpetpedagogy.wordpress.com - I add to this site now and then with the intention of disseminating information and hopefully helping a few people out. It has some articles and a whole lot of free excerpts and parts.
http://trumpet.music.unt.edu - UNT trumpet page. Find news and information about what's happening at UNT.
www.HSUTrumpets.com is the webpage of the trumpet studio where I did my undergraduate work.
The trumpet gearhead answers a whole lot of questions that most trumpet players have.