Yes, a Z68 motherboard is your best bet for a good chipset that can fully utilize the throughput of your SSD. I recommend the GIGABYTE GA-Z68XP-UD3P. You don't need PCI express 3.0 for a 580, it should not bottleneck at an x16 slot. If you have two 580s in x8 slots, you may bottleneck the cards, but probably not by much according to this x8/x8 480 review:
HARDOCP - Introduction - GTX 480 SLI @ 2560x1600 - GTX 480 SLI PCIe Bandwidth Perf. - x16/x16 vs. x8/x8
SLI 580? You will need at least 750w, recommended 850-1000w.
http://www.guru3d.com/article/geforc...-sli-review/14 So, spend a little more and get the 850w version of the TX series if you think you may SLI in the future.
That case has excellent ventilation, however I have added 4x 120mm Yate loon high speeds to mine and moved the large 230mm fan on top to the side of the case (blowing on the graphics cards). I get extremely low card temps on my SLI 460 setup.
You should have all of the cables you need within the motherboard box or the power supply box.
edit: You are also purchasing an unlocked processor, I recommend you get a heatsink and overclock it as those processors hit 4.5GHz-5.0Ghz easily. You can check out this list for HSF performance:
Xigmatek AMD Heatsink Temperature Comparisons - Gaia SD1283 FrostyTech Review