Good Post on Call to Action Buttons
Posted by ophir on December 9th, 2009
I just found this post from a couple of months ago that has a plethora of great examples of call to action buttons.
Changing the call to action button is one of easiest ways to improve your conversion rate.
Check it out:
http://www.smashingmagazine.com/2009/10/13/call-to-action-buttons-examples-and-best-practices/