Very good question. I don't know of anything specifically for truck conversions. I suspect there isn't anything since most t/c owners are at the racetrack. There is a national rally that you should consider:
www.hdtrally.com . I went last year and was the only t/c. But, it was a great time and everybody was real nice. We made some great friends. It's primarily people that use semi tractors to pull their 5th wheels. Very cool. They welcome anybody in any type of camper, even tents. There were a handful of people that came to do research prior to purchase. Maybe the more t/c's we get there others can see the benefits? I had lots of fun checking out all the cool trucks and setups. The educational seminars were helpful for t/c owners too. And there were some great sightseeing trips in the area. I'm planning on going this year and it would be great to have some other t/c's there with me. I can't stress enough how nice this group is and no matter what you are camping in you will be welcome. Every day happy hour is at 4:00 too. I rarely missed one, and I don't even drink. Hope you can make it.