I just became an expert in conjuration and am seeking something more powerful than a scamp to summon. What mages guild specializes in primarily conjuration spells? --- My Ambitionz az a Ridah; gt: Eidolon Qualm
It's been a while but I'm pretty sure it's in Chorrol. But don't forget there is still a few decent conjuration spells that can be purchased elsewhere.
I don't know how long you have been playing Oblivion but if you haven't had a look at the wiki yet then I strongly recommend that you do. After three years it is very comprehensive and of a very high standard. This page will help you with your current problem: