Here is a list of designers that will allow their graphics to be used in LOCKED format for your shares. I will update this as I research and if you find that I'm incorrect with a designers TOU...please let me know and I will remove them.
I want to encourage you though to be creative with your shares. There are TONS of things you can share without using graphics at all!
Annie Lang
Barry
Create with TLC
Designs by Trina Clark
Granny Art
J. Rett Graphics
Mail Montage
Outlaw by Design
Pixels by Judy
Primsy Doodle
The Graphic Shop
UF Designs