Greetings, artistampers! I've recently joined this group, because I've been making artistamps for many years. I thought I'd pass along my free resources...
I wrote this article on how I make faux postage using PhotoShop:
And I have a bazillion free sheets of low-res faux postage posted, which you might enjoy altering:
I also sell high-res digital faux postage sheets at Ten Two Studios.