Thinking back to the beginning, there was a very gruff narrator in the beginning of the game talking to Cole about being a detective and stuff. Did I miss where we find out who this is? I guess if I had to attribute my memory of this voice to any character it would be Biggs, but I'm not sure. Any ideas?

Yeah, it's Biggs - played by Keith Szarabajka. Guy's got a pretty distinctive voice so it's easy to pick out.

 If you go to the wiki http://lanoire.wikia.com/wiki/Herschel_Biggs it's stated there that it is Biggs. Given the voice work I'm inclined to agree with it.