Aww, don't devalue yourself *that* much! You're at least worth a few bucks.
You'll have to know what your budget will be and what focal length you want to go to, as wide angles are notoriously expensive, especially the ultra-wides.
If 16mm is wide enough for you, then I can highly recommend the DA 16-45, which goes for around $250 2nd hand. It's a fine lens that closely rivals the top lenses in image quality (IQ), but it is an f/4 max lens.
But if 18mm is wide enough, then why not just have the kit lens (unless you already have it). It goes for a lot cheaper still and has reasonable IQ.
But if neither are wide enough, then I'm afraid you'll be struggling to find a wider lens for anywhere near these costs, manual or auto focus. You may want to consider, however, a DA 14 f/2.8, which has good IQ also, built well and is in the order of $450-500 (I sold mine for $325 last year
). Other than that, then it's the Sigma mentioned above.