Redwood and Stormhorns work for pure class druid. Will ask @TheMinionOfArabel to try for nondruid members.
Could have them at some of the treasure sites. Fire by the lava in forest of Eyes, Ice memphits in the Stormhorns by the giant bones.
The Oasis in the Stone lands desert could have a water elemental in the water area, and any of the rest of them on the dunes.
Bard of quality, with a code to do no harm with her song. I recommend her for a seat.