How do you get more spells? I heard about the College in that city up north but is that the only place?

Where are all the argonians? The only city I have seen them in is the above mentioned city. I haven't been everywhere but I have not seen more than three.

When will I start seeing better heavy armor? I'm level 12 and all I see is fur, iron, steel, etc.

Oh and should I hang onto the amythsists I keep finding?