Sorry for the delay. For Twitter, we don't have an easy way to create a custom button right now.
For Facebook, you can create any image you want and then wrap it in a click tag, like below:
<a href="javascript:void(0)" onclick="jfbc.social.feedPost('Title', 'caption', 'description', 'http://www.link-to-shared-page.com', 'http://domain.com/image.jpg');"><img src="sharebutton.jpg" /></a>That will show the share popup window whenever clicked with your predefined title, caption, description, image and URL link.
I hope that helps get you started. There may be an easier way to do the Twitter share as well, but I'd have to investigate that further... so start with the above
Best of luck,
Alex
Custom like/share buttons
