So I was wondering, I hit level 18, and my intelligence is at 100, now, does that mean my magicka is capped at 300 now with my breton? Or does it constantly go up per level like health does? Also, if that is the case, is there anywhere to get good enchanted stuff from pre arcane university?????

Welcome to Cyrodiil, and to the forums!

I'm fairly sure your magicka is now capped - unless you use Fortify Magicka enchantments, that is. My Breton Mage is in the same position. As for enchanted gear, your best bet is to use the Sigil Stones found within oblivion gates - each one offers an enchantment, and some of them can be quite powerful. If you're not doing the main questline/have completed it already, just look for loot in dungeons

thank ya kindly! Awww, i was hoping it would keep going up like health, oh well. Thank god i just got that painters thing from the mission to get that guy out of the painting, it at least fortified my intelligence by 8! Ill have to do that enchanting thing then at the university, or the wizards tower, whichever, cuz some of the conjuration spells cost more than what i currently have! >_<

From UESP: Base Magicka = (Intelligence × 2) + racial and birthsign bonuses
So Base Magicka = (100x2) + (50x2) = 300, assuming you're playing a Breton with the mage birthsign.

Your intelligence can be increased with 'fortify intelligence' enchantments, which in turn will increase your magicka. And from memory, a higher conjuration skill means a lower cost for conjuration spells?

Yes this is true. Continue leveling your Conjuration (typically by casting Bound Dagger and sheathing it repeatedly) and the spells will continue to go down in magicka cost.

Edit: scratch that, wasn't thinking properly for a second.
Why is there no delete post button on these forums?

There used to be a 'delete post' feature. People abused it with "ghost bumps." A ghost bump is when you type a word, post it, and then immediately delete the post. The thread would be bumped up to the top of the forum but no one knew who did it because the post was gone. Moderators would issue warnings for it (when they were quick enough to catch the person who did it). When Bethesda moved to the new forums they got rid of the 'delete post' option altogether.

Heh, give 'em an inch...

The times I have done something dumb like post a reply on the wrong thread or some such, I simply hit the 'Report' button on my post and humbly ask the mods to delete my erroneous post. I don't do it often, but when I have so requested, our wonderful mods have always cast their 'delete' spell on my post for me.