www.Upwork.com: is the most widely used site for professionals (over 1.5M contractors), mainly for Freelancers (used to be Elance.com) Freelancers and contractors meet in this environment and negotiate based on fixed rates. Ranges from entry-level workers to highly skilled professionals

www.toptal.com: Do you want to hire top of the line professionals in different fields (Developers, Marketing Gurus, Designers, SEO Specialists, etc.) then this is the site you are looking for. Also if you are in that top group of experts and want to offer your services (great compensations). This site will match your level of skills with available projects and offer contractors only the right matches.

Guru:  It is a widely used site to find jobs because also lets freelancers showcase their past experiences. The main feature about this site is a daily communication they offer with all projects matching the skills you list in your profile

Jobs.smashingmagazine.com: A site mainly for developers and designers, has a very particular design, considered a niche type of site for professionals

Freelancer.com:  Also offering an amazing amount of projects and has a special feature, it will let professional compete and present a portfolio to battle for clients. Contractors can get a better idea of the capabilities of freelancers

Craiglists.com:  Freelancing sourcing is not the main strength of this site as we all know, but it can be an interesting source of local or remote works as requested in Major Cities

99designs.com:   This is also considered a special niche site for Designers. Contractors will send requests for specific design projects and freelancers will compete to prove their skills, contractor will then select the best work according to their criteria

Peopleperhour.com:  Offers a very specialized market mainly for Web Developers and different activities around this area like SEO, Graphic Design, Front and Back end specialist, etc. This might be the right match for that group of freelancers very focused in this type of projects

Freelancewritinggigs:   Are you a writer, editor, publisher, etc. or looking for one, then this might be the perfect match for your project, they say content is boss, giving some weight to your site might be a matter of getting some good nutrients from this site

Collegerecruiter.com:   As its name presents it, it is a site for students in college (or recent graduates) trying to find gigs for entry level or advanced students. There are skills in high demand from some contractors that are interested in very special talents young professionals or students have to offer

Ifreelance.com:   If you want to keep 100% of the money you make in your gigs, this is the site for you. It has a wide range of projects for writers, developers, SEO specialists, marketers, etc. This is what their moto is: “Find freelancers to plan , write , design , build and market your project all in one place”