Don't know if you have a preference on CPU's if you want the most bang for your buck you could get the best AMD CPU:
AMD Phenom II X6 1090T Black Edition
ASUS M4N98TD EVO AM3 NVIDIA nForce 980a SLI ATX AMD Motherboard
ASUS Xonar DS 7.1 Channels 24-bit 192KHz PCI Interface Audio Card
G.SKILL 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Dual Channel Kit Desktop Memory Model F3-12800CL9D-4GBNQ x 2 gives you 8 gigs
COOLER MASTER HAF 932 RC-932-KKN1-GP Black Steel ATX Full Tower Computer Case.
Total price of $650.63 all from Newegg.
You get a great case that will help to keep anything cool you want to put in it, a motherboard that can handle another graphics card if you want to later go SLI, a great sound card that will work with your BR drive or whatever you want, fast and great AMD compatible ram.