figures that represent the 4 elements Earth Wind Fire Water

air could be a mcfarland Raptor figure. earth maybe a Thing or a Giea Summons figure from Final FAntasy and fire can't go wrong with Human Torch also another water figure Hydroman SMC or XMC Iceman

It's called E-Hero Avian in case you want to look it up, it's only 4.99 at KB Toy Stores and is about 6 inches tall.

The yu-gi-oh figure is beautiful, I've never seen that one before, thanks!

Treebeard! That would be awesome, assuming you can find one Human Torch is cool, but he has boots and gloves so he looks kinda strange.

If you want a flying figure to represent air you might try some of the Archangels from the X-Men lines. If you don't care if they are a flying figure, you might try the invisible approach. There are several figures with translucent or invisible versions like the Invisible Woman and Iceman.

If you want to rock, there's The Thing and Clayface.

There's Treebeard from LOTR for wood.

And fire, you could also use the Human Torch.

You could repaint it to whatever color you want I guess, if you don't like green. It's also poseable and can be taken apart (no clue why, lol)

And for Earth, how about a Marvel Legends Thing figure?

Well, There's this cool Eagle-thing from the Yu-Gi-Oh line, let me get you a picture...