Replace WordPress footer credit with Designer credit?

Hi, back in February it looks like you offered this option to someone. My client LOVES her site and is fine with the theme credit staying but thinks it's really weird that she can't point to her designer in the footer. Can you help me out with this? All I'd like to do is replace the WP credit and link with the one to my website. I'd also like a reminder of where the copyright info is entered. Thanks