Since you're building this system specifically for gaming, as it was mentioned, you can go with a quad core processor and will lose next to no performance. This means you could go with a cheaper AMD Phenom II x4 if you wanted as well.
Don't forget about the new i5-2550k, which does not have onboard video but has a slightly higher clock speed from the factory.
http://www.newegg.com/Product/Product.aspx?Item=N82E16819115230
I'm personally using the i5-2500k and have been thrilled with it. I have used AMD for years, with the exception of a few systems, and have always been impressed with their value. The 2500k though is another story all together, it is priced very competitively and it seems to really blow the competition out of the water. Typically, you don't need to spend $200 on a motherboard, for either system, to get great results. If you cap your MB pricing around $150 or so, I think you can find a terrific board that will let you OC at will and will be very reliable.
When it comes to deciding on as SSD, it is a noticeable improvement in boot and loading times over a standard platter based drive, but it is also something you can add later if you wish. If you are going with an SSD though, I would suggest going higher than a 60GB. I'm using a 120GB and believe me when I say, it fills up quick! When you consider that some of the new games easily use 10-20GB of space for a single install, plus you only get 112GB out of a 120GB because of the way the drives are engineered, and that windows 7 isn't exactly tiny, the more space you can get on an SSD the better. The prices are dropping pretty rapidly now, its quite easy to find a "high-end" SSD for around $1 per GB, and this should be closer to $.75 a GB by the end of the year.
Anyway, Sosofm posted a decent system for you. I would suggest putting as much into your video card(s) as possible, as this is where gaming systems are made. A AMD 7970 or 7950 are tops on the market right now and offer some awesome performance! I would suggest going with one of the all-in-one water cooling systems instead of air for your CPU, they are much quieter and very very effective, not to mention easy to install.
Good luck with your system!