How to get rid of footer credit (or theme credit  theme_credit()?) at the bottom of a WordPress blog?
How to delete WordPress Blog credit at bottom?

Usally it is found in the “footer.php” file, but when deleted it can cause your blog theme to mess up.
A simple solution is just “comment” it out. This should keep it from showing without deleting the theme code. Notice the <!– character added twice

(Example)
Before

  &copy;
                <?php echo date(“Y”);?> – <?php bloginfo(‘name’); ?> is proudly powered by <a href=”http://wordpress.org/”>WordPress</a><br/>

  <?php /*Please leave 1 credit line to the theme designer. Thanks.*/ theme_credit();?>

After:

  <!–&copy;
                <?php echo date(“Y”);?> – <?php bloginfo(‘name’); ?> is proudly powered by <a href=”http://wordpress.org/”>WordPress</a><br/>–>

  <!–<?php /*Please leave 1 credit line to the theme designer. Thanks.*/ theme_credit();?>–>