The Commonlands and Karanas are nice places to fight as a druid. There are lots of animals and they are outdoor, so you will be able to use all your spells. In addition, there are spider silks and pelts that you can sell to other players for nice cash. You can also forage Plains Pebbles and other items which sell nicely in the bazaar. After about level 10 or so, I would recommend Crushbone or Kurn's Tower for simplicity. At 15-17, I would make my way to Paludal Caverns. If PC is too crowded, you can always root rot the fiends on the path behind the first camp. Find a nice high level druid in the game, and ask them what they did. They might even pop a few buffs on you just to be nice.
Send me a tell in game... If you do not play on brell, you will need to type ;tell brell.blitzwolf and then your message... I can be more helpful if I could ask you some questions... like which expansions do you have, do you not want to fight in crowded zones, do you have all your spells, etc...
Blitzwolf Thunderpaw, 54 Halfling druid of Karana on Brell
Now with a Hole raid under my belt