5773 Simple Add Text & Link Script

I know there is a unix command for this, but I'm also sure a simple perl script could do the trick. What I need is to be able to go to all html pages within a folder ([login to view URL]) on a hosting account and globally add some text and a link at the bottom of all html pages. something like 1) find the close body and close html tags and 2) add this href & text bla bla bla above it .