FYI: I'd be wary of recipes on any site that allows the public to submit recipes. I've seen some nasty stuff on the recipator, and even made a few terrible tasting batches with recipes I didn't have the wherewithall to really anaylyze prior to brewing it.
For a first porter attempt (or a first attempt at ANY style) I would suggest using a simple recipe with no crazy fruit, nut, spice additions. Get the base recipe under control, then start tinkering with it.
Ground Fault Brewing Co.