Changing the URL of the "Register My Account" button

I know I have started a few threads, but I really need help.
I would like to change the URL of the "Register My Account" button.
I figure that it is hard coded somewhere.... And I cant find it but I would feel comfortable changing it.
I would like it to go to the address...
The site needs to be good to go by tomorrow.. ~~~~ YIKES~
Thanks so much in advance~