IE styles not being picked up. Missing theme.php!

I created a Bartik subtheme and wanted to edit the ie.css. I soon realised that it wasn't being picked up. It wasn't listed in the .info file and when I checked the original bartik theme folder I realised that the ie stylesheets are being called from the template.php file, which for some reason is missing from my subtheme folder! I have no idea how I managed to do this. Copying the theme.php file to my subtheme, gives me a white screen of death. Removing it, takes me back to my styled, customised site.

What are the implications of not having a template.php file in my theme? What is the best way to call the ie style sheets if I don't have a template.php file?