It is totally possible. I'm into a lot of tech stuff so here are some suggestions:
It is highly
unlikely to find a new ultraportable laptop under $500, except possibly under the brand Averatec. They sell their laptops at bestbuy, staples, etc and as fall as I know they are the cheapest in 12inch ultraportables, however the quality of the laptops are not that good.
For used laptops, there are many options though I would not go to Dell Outlet. Rather, I would check out http://www.ebay.com
. Routinely, users sell nice older ultraportables on these sites. But, be sure you don't get ripped off on eBay. It is unlikely you will get ripped off on Craigslist, but you'll be meeting in person.
For online discounts on laptops, I would recommend surfing http://www.boddit.com
. I have used it for other stuff because I already have a laptop, but they mainly have deals on everything.