Thoughts/Advice for first rig (newb)

I seriously hate making threads, But jesus christ there is SOOOOO much information on here that it's just TOO MUCH. And each one at times goes on for ever and ever...

Currently I'm using my main desktop, which is mostly new'ish parts.
ASRock Z77 Extreme4 LGA 1155 Intel Z77 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard
SAPPHIRE Radeon HD 7850 OC 2GB 256-bit GDDR5 PCI Express 3.0 x16 HDCP Ready CrossFireX Support Video Card
and an ancient PowerColor AX4850 512MD3-DH Radeon HD 4850 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready CrossFireX
that I threw in there figuring "Why the hell not?"

I still have my
GIGABYTE GA-965P-DS3 LGA 775 Intel P965 Express ATX Intel Motherboard
an E6600 cpu and some memory, possibly an old HD someplace.
I'll need to grab a PSU.

I don't have a lot of cash on hand right this moment but it would make things easier if I could get a doable plan of action together.

I guess really what I'm asking is what GPUs grab that are viable at low cost if grouped together so I could start to pull in some thing to build upon. I'm un-sure about Risers but I know I WILL need them.

Again, I hate making threads that seem pointless and stupid but I am truly trying to figure this out and sadly I have both Blonde and Polish genes >.>