Buttons Not Showing, Only Text

I am having a problem where the buttons on my site all of a sudden stopped showing, so I looked at the error log in my cpanel and saw this error:

File does not exist: /home2/parts5/public_html/button_sprite.png, referer: http://store.commoto…lmet-clone.html

I tried inserting button_sprite.png into skins/basic/customer/images, but this still didn't allow my buttons to show. Has anyone ever had this problem or possibly know how to help? Thanks in advance.