The Morag Tong guildhall is up near the Hlaalu headquarters. Start at the Mage's guild and walk up past the Fighter's guild. A bit further on to your left there's some stairs - go up and keep going in that direction until you reach the Hlaalu manor, then turn right and the Morag Tong is around there. Sorry for the complicated instructions but I can't remember what direction the place is so I can't use a north/south type thing
There are also Morag Tong guildhalls in Ald-Ruhn (under Skar) and Sadrith Mora (a bit past the council hall) [img]smile.gif[/img]