Hey, I'm not an expert on cars or engines at all but I do know that my 914 has got a leak on the oil filter mount and an o ring needs to be replaced. Does anyone know what it takes to replace this and how much it might cost if I brought it to a professional?

Thanks for the help and if anyone has pics that'd be great!

Assuming that this is a 914-4, the O ring is part of the oil filter. Replace the oil filter!

Also check to see if the O ring from the previous filter isn't stuck to the filter mounting surface. I've seen that happen when the O ring wasn't oiled before installation.

The filter has a flat rubber gasket, not a true O ring. The oil you see on top of the filter is probably come from somewhere else like the oil pressure sender above the oil filter.