craftgrrl | metal primer & spray paint

A quick question for all my fellow craftrrrs....

I recently found a lovely little antique brass shelf (the kind you often see in bathrooms to hold towels, etc) that someone had discarded in an alley (criminal in my opinion), so I decided to rescue it, clean it up, and use it in my own bathroom. The only problem is that it's rusting a little bit (since it's been weathered outside I'm assuming), so I need a type of primer, sealant, or varnish for metal to coat it and prevent it from rusting further and then also to protect anything I may want to put on the shelf. In addition to that, I'm also wondering what would be a good spray paint to use on top of the first primer layer to make it look newer and give it some more color. Right now it's a brassy-gold, and I'd like to stay with that color. If you have any suggestions of products, let me know! It's greatly appreciated!

p.s. I will do my best to put up pics after I have finished fixing it up! :-)