Picked made a great list. SolA is a cool zone with some great loot opportunities. It can carry you and your group for quite a while as it increases in difficulty once you enter the castle.
Mistmoore is another good zone for XP. I always enjoyed doing Unrest at around your level. You can do the Fireplace as a camp spot and get some good XP and decent loot.
Don't forget to consider The Crypt of Dalnir in Kunark as well. There are some great zones in Kunark which people rarely go to. Mines of Nurga and Temple Droga also come to mind in the 30's. They are challenging but neat zones.
__________________
-----------------------
Fearstalker - Enchanter
Guild Leader of <Taken>
-----------------------
|