There are a couple of GMRS repeaters in my area that are starting to sound like Amateur Radio. CW ID every 15 minutes around the clock and controlled traffic nets, et al. They're openly soliciting communications with anyone who hears them and wants to play along.
With that said, my experience has been that most GMRS users didn't buy the radios to chat with random people. They use the radios for camping, hiking, outdoor pursuits, off-road ATV operations, farming, small family business communication, and personal comms between family members. GMRS has never been used like CB radio -- but I'm not sure if that's not slowly changing.
Check the FCC database at:
License Search - GMRS License Search. Search by city name or Zip Code and see who has an active license. You can also monitor the 22 GMRS frequencies and try to communicate with them.
www.myGMRS.com is a database of GMRS repeaters across the country. Lots of information there including contact info for the owner, cost sharing, and if open communication is acceptable there.
You might want to post something in the GMRS/FRS section of this forum. You might find some locals there.
Good luck, and have fun!