Your build is similar to my Haswell build (full specs in my sig). Only i have GTX 760 in there.
With your build, you can play almost any game with high/ultra settings @ 1080p with 60+ FPS. Only the latest AAA titles that require 16GB of RAM may not work on your PC.
For getting games, you can start from Steam,
link: http://store.steampowered.com/