Where is J`skar?

Hint:
Talk to Volenaro(a member of the guild).Raise his dieposition first.He will tell you what to do

well,I`m a newbie so how do I raise his disposition?

Through speechcraft.You see that face icon in the down left corner?Click it and play the circle game.The more points you have,the better chance you have that he reveals you some important information.Don't worry,the game is quite easy.

Or you can use a Charm spell.

Or Bribe him. :-p

the persuade mini game is very easy and somewhat fun. But yes, if you have lots of gold bribing is very easy.
Charm is easy and even if you can't cast the spell, charm scrolls are fairly easy to find.

Just keep working on those Mages guild initiation quests!

(sort of 'cheaty' tip/spoiler for giving 100 disposition below)






As soon as you get access to the Archane University you can create your own spells. Then you can make a 'Charm 100'-spell that last for a second or two, and it's very cheap and requires almost no skill or power to cast. When you have this you don't have to pay another bribe or play another minigame again, since using this spell causes 100 disposition. Also very handy for getting the best deals from merchants.