Within the college of winterhold

talk to the woman who first initiated you (not the one who walked you in, but the one who makes you go find the old mane) and ask her where you can learn more spells and she will tell you, but I think ones avaliable are either based on skill lvl or how much they like you.

there is an NPC for each school... most I believe live in the other bunk section (the name escapes but not the Hall of Attainment) as these are like the tenured mages

Thank you.