sorry to disagree with everyone, but if you are worry about games and you haven't done any oc before, I would recommend you to get a nice video card.
OC is not hard with the right hardware and software. But today's CPU, assuming you are spending more than $100 on the cpu, don't really limit your gaming experience, video card plays a much bigger role. So OC may not help you too much in gaming, especially if you are not going to do too much OC.
If you want best bang for the buck, yeah OC will definitely give you that. You can get a $68 cpu and OC it like a $300 buck cpu, but that's only if you have the right mobo, memory, and cpu cooling. In the end, the time you spent may not worth the saving, but for people like me, that's just something fun to get the max out of the system. But again, from a system point of view, your PC performance is determined by a combination of factors, and CPU itself will not determine all your system performance, and in gaming, video is a much bigger factor. (you can OC video card as well)
So I'd say OC is a hobbit, and I would recommend it if you enjoy messing with your system and doing lots of reading and research. If you don't, spend the money and get it over with.