www.EmbLibrary.com has oodles of embossed frames in all shapes ready to add whatever you want inside, and instructions. Not free but really nice.
Here are a couple of bases. Do you want frames for the letters to go inside or bases for the letters to go on top of?
thank you so much for all the imput to help with designs to put initials on towels.
Grammy
I have a set from this site for free
http://www.motherhenquilts.com
Didn't find any free ones - but these aren't too bad.
http://www.embroiderydesigns.com/...
http://www.embroidery-designs-sho...
http://www.embroidables.com/store...