Ok, Here is the problem.. I am suppose to get the black Book from the tower. Problem is I had gotten the book at the beginning of the story line (stole it when assistant walked in to get somthing so now I cant complete the quest line.. is there a workaround for it or a console command through pc that will complete that quest?
If you're on PC you should be able to use a setstage command to close the quest. Just look around on the wiki and you should find the specific command. As for the issue itself, I've encountered this as well; it starts when the madman runs up to you, correct? I'm reasonably sure it's just a bug. Don't worry about it.
EDIT: Oh, wait. You say you can't complete the quest line? The Dragonborn main quest? That shouldn't be the case. The Tel Mithryn Black Book has nothing to do with Miraak. Can you use the Black Book, and gain the hidden knowledge?
This just happened to me as well. Xbox 360 version. I already had the Black Book from Tel Mithryn and speaking to a madman triggered the quest to get the Black Book from Tel Mithryn.
I was right outside Tel Mithryn at the time. I'd just looted the Deathbrand chest nearby, and then fought a Lurker on the beach. The madman seemed to appear during that fight, sort of on top of the Lurker. When it died, he was standing right where it was.
Went bacl to Tel Mithryn and tried a few things, in case it would clear the quest, but nothing worked. You can't drop the book to pick it up again. Taking to Neloth about Black Books again doesn't help.
In short, I just re-loaded my savegame from before it happened, lost a few minutes of progress - and vowed not to get into any more conversations with random madmen :)
This thread is more than a year old the dates are on the bottom left of comments. But unfortunatly theres no way to get rid of a quest on a console so if you have done it already and you see the Madman avoid him, or if it's too late reload a save before getting given the quest a second time.