Here are some frame sliders i plan on getting from Lockhart phillips. They will mount on the frame right under the tank ( where it sticks out past the frame).
I had made some simular to this for my race bike years ago, it was basically HDPE plastic, cut into a knee puck shape, receased mounting bolts. I had to drill holes in my frame, and insert a rivnut ( a threaded rivet nut ), and bolted the right on. This would protect the tank, mostly, and the frame.
Here is the lockhart version:
(http://usera.imagecave.com/ratz/Lockhart_Phillips_Ricochet_Frame_Sliders.gif)
If you look at my avatar, below the tank, is my version.