1. Freelancer

Freelancer (formerly GetAFreelancer) is the world's largest outsourcing and crowd sourcing marketplace for small business. There are 2,451,843 employers and freelancers connected globally from over 234 countries and regions. Freelance projects cover fields of software, writing, data entry and design right through to engineering and the sciences, sales and marketing, and accounting and legal services.

2. Joomlancers

Joomlancer is regarded as one of the best places for Joomla experts to get high paid jobs. Projects on Freelancers are mainly related to Joomla and Mambo, mostly customizing Joomla! templates or developing extensions, but you still find other types of projects here like design, translation or something like that. Joomlancer is said to be less competitive compared to other freelance marketplaces, only ten projects are posted daily yet the fee is quite interesting.

3. Elance

Elancer, based in California, has been available on the World Wide Web since 1999. Elancer tends to attract employers with a higher budget because of the 10% upload fee per project. On other sites, they normally offer free uploading. It might be good news for freelancers working in more developed countries like US or Canada as they don't have to compete with freelancers from less developed nations such as India, China and Vietnam.

Generally speaking, Elancer is a good marketplace for employers with big budgets looking for quality freelancers.

4. Odesk

Odesk has an online tracking system, which makes it stand out from the crowd. This system checks employees' work every ten minute so that their work is assured to be under progress. This freelance marketplace is different from other sites, which is a good for employers who prefer to pay per hour rather than by project.

Odesk does not charge membership fees to providers. They charge providers 10% of the project fee paid to them instead. Employers can use Odesk for free. Also, Odesk has an online ticket submission support form, which usually takes around one day to get the ticket request submitted back.

5. Scriptlance

The most noticeable thing about Scriptlance is its free registration and free monthly fees. In general, this is a competitive marketplace with hundreds of projects posted every day and thousands of freelancers bidding. Scriptlance provides some withdrawal options including E-gold. Another good thing is its low commissions, which is only five percent of the project amount (minimal fee $5).

6. Vworker

RentACoder is now renamed as vWorker freelance marketplace which stands for "virtual worker". The reason is that freelancers joining this site are not only coders but also experts from other fields like design, writing, assistants and more. Vworker has had some changes, one of which is the payment method called pay-for-time that lets you do both. This method saves money and helps both buyers and sellers have more flexibility in their work.

The site has changed its domain with the resulting negative impact on the Google page rank of vWorker now (it's now quite low). Some people feel hesitant about vWorker due to this reason. However, if someone has experience with Rentacoder, vWorker is absolutely no different in quality.

7. Guru

Guru is one of the world's largest online marketplaces for freelancers with more than one million registered members and more than 8000 projects posted monthly. This site focuses on three main areas: Technology, Creative Arts and Business but over 220 skill-based service categories. The website was founded long time ago in 1997 and operated in Pittsburgh, Pennsyvania now.

8. Project4hire

Project4hire is free of charge for clients to post projects and for contractors to bid for those projects. Only a small fee is withdrawn from the contractors' projects.

You will find here OsCommerce Programmers, Wordpress developers, vBulletin skin designers, Joomla coders, Drupal programmers and xHTML/CSS coders and more.You can also find translation services and translation jobs. You can find plenty of freelancers in Project4hire.

9. iFreelance

In iFreelancer, registered freelancers have to pay membership fees for the services. The basic membership is $4.69 per month, silver for $6.95 per month and gold for $9 per month. The higher the membership, the more benefits you get. Especially, freelancers don't have to pay a commission on what they earn. This site has got a lot of trust from buyers and freelancers and built a strong relationship between them.

10. BizReef

Bizreef is an Israeli owned Freelance Marketplace launched in October 2007 by MeVideo Ltd. The coolest thing about Bizreef is that it has an Escrow system that guarantees that freelancers will receive order services as well as protection of their rights. The payment is kept in Escrow and just released after freelancers approve their delivered work. You can feel safe with transaction. Plus, Bizreef provides a bunch of projects every day that attracts many freelancers in different parts of the world.

I hope that these sources will give you the best freelance job opportunities worldwide. If you happen to know any good freelance marketplaces, feel free to share with me and other people. For those who are just starting to look for freelance work, I guarantee the reliability of them and suggest you try them. What do you think of them? Leave some comments!