The two websites I find the most of my work at the best rates are Freelancer (previously GetaFreelancer) and oDesk. None of these two sites charge any registration of signup fee and have very reasonable commission structures. In addition, both these sites have easy earning withdrawal methods that allow you to have access to your earnings on a weekly basis. Both Freelancer and oDesk have a waiting period on first withdrawals to prevent money laundering practices.
Special membership packages are available where a monthly fee is charge that allows you to place more bids, and save on commissions charged. However, for the novice or the person just starting in the freelance writing world, buying memberships are not that important. I always recommend writers to first earn a few dollars that can pay for the membership. An important question you need to ask yourself before buying any membership packages, is if you will utilize the benefits these packages present to the fullest? It is penny wise pound foolish to pay $20 for a monthly membership plan, but you only pay $10 on commissions every month. 
I have come across a site where you pay a monthly fee of about $45 per month and they “guarantee” you work at a rate of $10 per article. In addition, in order to be able to join this particular site, you need to buy a “training” package and after successful completion of the course, you are eligible to receive work from them. This is just one example of the thousands that exsist.Frankly, I can not help to wonder why a client would want to pay $10 per article if he can get it at one of these very successful freelancing websites mentioned at a fraction of the cost.
Should you pay to register or signup with freelancing websites? I really can not see why you would want to. There are numerous reputable and very successful freelancing job sites where there are no fees to pay that truly provide excellent opportunities to start a career in the freelancing world. 
