Most commercial and DOE sites have given the exam in the past, but there aren't as many taking them in a given year. I work Browns Ferry, and drove past Sequoyah and Watts Bar on my way to Oak Ridge to take my exam. I was the only person that took the test there, the other was a no-show!
NRRPT will have to give you the info on where they are testing this time. There is a lot to study, and you need to be conversant on dpm vice uuCi as the base units for contamination.
I studied the books listed on the site (Gollnick was the best, Cember next best, the MOE handbook online here was best for DOE introduction.)