I am building a skelton structure out of some angle iron, and I'm wondering
about a decent method for painting it. It will be indoors and doesn't
really *need* a paint job, but I'd like to paint it anyway.

The angle iron has a coating on it from when I purchased it, sort of a
grayish color. While I have wire brushed coatings like this off in the past
for small jobs, there's too much iron for me to fiddle with the brushing
this time; is it generally okay to paint over the stuff that angle iron
comes already coated with, and if so, should I use a primer first?

I'm also looking for a recommendation on a "decent but cheap" spray paint;
I'm not looking for an automobile finish, but want something a little better
than $0.88 Walmart rattlecan; ideally something good that's two or three
bucks a can.

Thanks for any suggestions,

Jon