Not really much of a spoiler, but I'll hide this anyway.

I can't remember the Quest names, but one of them involves retrieving a book, "Souls Black and White"?, and the other is similar. They both point to the Sightless Pit, not far South West of Winterhold, up in the snowy mountains. When I enter the Sightless Pit there's not much in there, just a door which it says is blocked from the other side. I've wandered around a bit, trying to find other entrances, but I can't find anything. Clairvoyance always leads me to this door, so I'm rather confused.

If I am missing something then I'll keep trying, but if this sounds like a bug to you then I'll just forget the Quests. Perhaps try them again with my new Character who I started last night.

Thanks.