I carry bumperstickers as well as buttons-- searches list both stickers and buttons.
You can pay by credit card via Paypal (you do not need a pre-existing PayPal account to select this option) or by check (be sure to enclose your order). Email me directly [your order will be emailed to me when you finalize it] if you'd like your order to be delivered at a con. My email is NancyL (at) panix (period) com
Vegetables are what food eats (Another Random Slogan)
Buttons are 2 1/4" diameter. Stock buttons are xeroxed from my calligraphy, mostly on patterned pastel paper. There are a few solid and black backgrounds. Both the calligraphy and the backgrounds are chosen for legibility. Let me know if there are any colors you especially do or don't want included.
New Slogans!
30 new slogans added in April, 2012
My blog is Input Junkie.
Contact Nancy Lebovitz to discuss anything you want; she's friendly. This includes discussing the site, of course. Or contact Joshua Kronengold, who did most of the [perl] CGI and HTML work on the site if you want to discuss similar work [He's not at all cheap, but is good and fast].