So I finished the college questline, I'm level 15 and all the npc's are still selling novice and apprentice crap. I've leveled to the point where all my spells are useless and I can't find better one's to replace them. The only decent spells I was able to find were some destruction spells... Is there anywhere else I can find better spells. My character is horribly gimp for his level now, and its quite annoying....

My skills are 57 destruction, 38 illusion 38 conjuration, 35 restoration, and 30 alteration. Mostly, all I can find are novice spells mostly, not even any apprentice ones...

The higher level spells are available from various vendors, but not that easy to find. If you want to see the complete list of vendors spells, look here (SPOILER):

http://www.uesp.net/wiki/Skyrim:Spells

If youre looking for the same diversity and usefulness as in previous titles, you are out of luck.

There are only a handful spells left, and most of them are next to useless on higher levels.

I beleive you need skill of 75 to be able to buy expert level spells and 50 for adept spells. I'm on level 39 with destruction of 72 and restoration of 60 something and haven't seen any expert levels spells for sale.

You don't get access to high level spells until your skill levels are high enough to cast them. At level 15 there's just no way you'll find a book of Wall of Storms or Paralyze. Just gotta keep playing with what you have, level your skills up and eventually you'll be high enough level to buy them.

^^^^

This. Until your skill level reaches a high enough level, the spell tomes won't be added to the vendor or loot lists.

Uh the college people will sell you whatever level spells you can reliably cast. That would be adept level for your destruction and apprentice for everything else. I picked up expert destruction spells at 70 from Faralda in the college.