99designs is a fabulous idea. Where else can you get such a broad cross-section of talented people all working on your project at once, and you pay a very reasonable price for the design you like the best. I've tried other online logo design sites, and even individual Craigslist freelancers. Nothing gets you the results and the choices 99designs gives you for the money.
If you're new to 99designs, you'll probably start out with the basic contest. I did also and had about 20 or so poor to OK designs in the first 48 hours. After I "Guaranteed" there would be a winner, I got the serious designers involved and had over 70 great designs 24 hours later. Ultimately I had over 100 designs. The biggest problem I had was trying to decide which great design I wanted. That's where the "Create a Poll" comes in handy, and I had a few friends and co-workers vote on my initial choices to help me decide. In my case I feel there should have been at least 3 winners.
I know this is probably beginning to sound a bit like an infomercial, but I have no financial relationship to the company. Just a great experience. I'll be back!