What level of vid editing are you doing and what apps? Whats the monitor resolution and what type of games? This will help with a GPU recommendation.
I'd lean towards the i7 860. $230 at microcenter.
This could work for mobo and PSU $170 amir
http://www.newegg.com/Product/ComboDealDetails.aspx?ItemList=Combo.435346
Lots of options for ram, just a quick pick. $100
http://www.newegg.com/Product/Product.aspx?Item=N82E16820226154
Pick a case you like the looks of. They all do the job of keeping your stuff in one place well and if you're spending more than $40 on the case, airflow should be good enough. The aesthetics though only you can make that call on and you have to look at it.
Depending on how aggressive of an OC you want, I can look for a HSF also. Not sure what the current go to is for price/performance. I'll do some digging.
Edit:
Microcenter has the Hyper 212 Plus for $20. I don't see how you can do better than that. Its a very good HSF. You can do better, but you'll be into the $40+ range.
http://www.frostytech.com/articleview.cfm?articleID=2419
HDD 1tb Samsung F3 $65:
http://www.microcenter.com/single_product_results.phtml?product_id=0340562
Looking further at the MC site, looks like the HDD, Case, CPU, and HSF are all great deals at mc. Mobo is about the same at either. And for the GPUs, ram and corsair PSU, newegg is much cheaper there. Antec and OCZ look to be about the same at both.
For just the little extra for the ram, might be worth it to just get it all at MC if you're careful. I wish I had one close by. I've got a 2 hour drive to get to the closest one. Not worth the savings in gas cost for just that purpose, but maybe I'll have to find another reason to be over there. Those are some great deals.