I could suggest 2 builds:
1) Intel Core i5 2500, H67 Gigabyte/ASUS Motherboard, 8GB DDR3 @ 1600MHz G-Skill Ripjaws X or Corsair Vengeance, Cooler Master HAF 912 Plus Case, Corsair TX750 V2 PSU, Crucial C300 SSD or Corsair P3 Series, EVGA GTX 460 1GB, Samsung F3 1TB HDD.
2) AMD Phenom II X6 1100T, ASUS M4A87TD/USB3, 8GB DDR3 @ 1600MHz G-Skill Ripjaws X or Corsair Vengeance, Cooler Master HAF 912 Plus Case, Corsair TX750 V2 PSU, Crucial C300 SSD or Corsair P3 Series, HIS HD 6850 1GB, Samsung F3 1TB HDD.
Same thing, only different flavors of processors/motherboards/video cards
1) If you want to Overclock your new PC then you'll need a P67 Motherboard instead of a H67
2) If you want to do Crossfire you'll need a 890GX/890FX Motherboard (AMD)
3) Depending if you want to do Crossfire and which cards will you be using, then i'd suggest a bigger PSU, probably a Corsair AX series.
4) If you want an aftermarket cooler, i'd suggest a Noctua NH-D14 (Air) or a Corsair H70 (Liquid)
5) If you want a better audio experience (music/games), i'd suggest an aftermarket Sound Card, ASUS Xonar Xense.
If you need any other things, just ask
EDIT: for the 1st build, you'd have to wait until april for the new revised motherboards with H67/P67 chipsets arrive to the market