I read an in game book earlier today that had placed the events of the first four games fairly close together. I believe within 50 years of each other in the third era.

But this made me realize, I have no idea what time I'm playing in. Keep in mind, I've just started playing Skyrim seriously very recently.

I know its in the Fourth era, approximately how many years after Oblivion is Sky rim?

Everything is here: http://www.uesp.net/wiki/Skyrim:Skyrim