Tom's did an article on easy overclocking of AMD and Intel CPUs on a Budget. I highly suggest reading it. It's very informative and details all the steps involved. I'll link directly to the page where it begins with AMD CPUs, starting with the PhII X2 550. The steps shown apply to all Phenom II's.http://www.tomshardware.com/reviews/overclock-phenom-pentium,2366-6.html
Though, I do prefer the step-by-step method of increasing multipliers and voltage as necessary, which is outlined in this article:http://www.tomshardware.com/reviews/phenom-overclock-athlon,2161.html
As far as the video card is concerned, ATI Overdrive in the Catalyst Control Center has an Auto-Clock feature that will find a solid and stable OC for your GPU. You might be able to get more than it recommends, but it's a great start and a very simple "1-click" method.