Digital BW, The Print

I recently saw some posts regarding AN glass and I am trying to find a
supplier.  I have an ArtixScan 1100 from Microtek (Support from Hell?
- No, just NO support.)  I sometimes scan up to 8x10 sized negatives
and transparencies and would like to avoid newton rings.  I have tried
using borders made from plexiglass or similar materials to raise the
image off of the glass carrier, but have not had much success.  Any
ideas would be very helpful!

Thanks,
Patrick Donegan, owner
Digital Eyes Custom Photo & Digital Imaging
Pleasant Hill, CA