I use MS Publisher and make my own. I use the poster publication and re-size it to 24 X 24.
I just bought some clear laminate on a roll today at WalMart to cover it. It's located with the contact paper. I'm mounting mine on foamboard and I go to Home Depot and get free 5 gal size paint stir sticks for handles. I've done this before...LOL.
MKM