Jessica over at How About Orange posted a thumbtack tutorial a while ago. I finally got around to making some at Christmas for both myself and for J. If you want to make some, head over to her site and follow her instructions (I won't post them again here). I will mention that normally I'd suggest using plain, old silver thumbtacks but I went with the multi-colored ones since they were .20 cents for a big box at JoAnn's. You don't really see the tack part unless you look at the thumbtacks from the side anyway.
The fabric I used here was from JoAnn's - the small squares used for quilting. This fabric worked just fine but I think in the future I may go with higher-quality fabric that is a bit thicker.