Rectangular magnets are available in Ann's CafePress shop.
There are a few circular magnets, but most images don't fit that format.
Magnets have a metal shell with a wrapped edge and a plastic covering.

Sample Magnet

Visit the shop and click on the "Browse by Product" dropdown to search for magnets.

Square magnets are also available. They're similar to the rectangular CafePress magnet shown above but made by Zazzle. Visit Ann's Zazzle Shop to find high quality magnets featuring her square format art.

Click on any image to see the magnet on Zazzle