Alternative platforms for freelancing include Elance, oDesk, Freelancer.com, and 99designs. Spend some time vetting the various platforms to get a better sense of what else is out there. That said, Fiverr and Upwork are usually ranked in the top five.
As you go through each platform, you'll notice that some offer skills tests to help source the most talented freelancers. Taking these tests can help set you apart from the pack. And some clients might even require them.