I have a Trassas T-Maxx 2.5 truck that has barely been used. Bought last Christmas
I don't know where to go to sell it.

I would go the for sale section on here and list it here. If no interest here, list on other forum sites, and pics are always a good thing.

Traxxas has a swap and sell section on their site also.
Many places to list it.
One of the best it right here on Hobby Talk.
http://www.hobbytalk.com/bbs1/forumdisplay.php?f=144

ebay is the best way to sell anything