I have several draft posts that I never got around to putting up. This one is from 8/6/2011.
Here’s a list of the main places to grind. It is based on the amount of xp per kill. This list is not complete.
Tenacious Frost Giants, north and west camps: 800k-1.1m*
Kobolds: 800k-1.2m
Tenacious Frost Giants, gate camp: 1-1.2m*
Goblins: 1.2-1.8m*
LSM Fire elementals: 1.2-1.8m*
Wandering spectres: 1.2-1.8m*
Trees: 1.2-2m*
Sirens: 1.7m
Bandits/Henchmen: 1.7-2.2m*
*HnG items through Chef Lukkif or other.
Everquest Online Adventures 
It’s interesting how the popularity of xp camps evolved. I remember when TFGs were the big thing, then goblins, and finally trees. I felt the frogloks were a very underrated xp spot. It sucked because the location was so far, but I think the xp was around the same as gobs. Someone please correct me if I’m wrong.