http://us.ncix.com/products/?sku=71114&vpn=P8Z77-V%20LK&manufacture=ASUS&promoid=1368
This ASUS board offers a good amount of connectivity and is reliable and relatively cheap.
For GPU, you could crossfire 2 7850 or 7870. Getting a single high end card is a better option though since there would be no issues with SLI or Crossfire scaling. For single card, I would look at the 7950 Boost or the 670. The 7950 Boost offers a lot of the performance of the 670 but is quite a bit cheaper
http://www.techspot.com/review/603-best-graphics-cards/page12.html
You can look through the review to check for performance in the specific games you play. The review used the latest drivers and prices form both sides. The end chart is slightly misleading so you should read through the reasons they give for their choices. The 7870 should have take the 200-250 bracket at $240 since it performs better than the 660. The 660ti should also have lost to the 7950 Boost since the 7950 fits right into the 250-300 price range @ $300.