First off, your work functions are clearly a hell of a lot better than mine. We're lucky if they buy us cookies for the meeting room...
I'm also in the process of building a core i7 system so here's what I've picked up along the way. You need DDR3 RAM, preferably in a triple channel kit. The memory must also draw less than 1.65volts, higher voltage RAM might fry Core i7 CPUs. Any PCI-Express graphics card will work, so its just a matter of picking one that fits your needs/budget. I might recommend an ATI 4770 as the sweet spot at the moment. As for hard drives, just go for any SATA drive that fits your capacity needs. I'm going for a Western Digital Black 640gb. As for cases, I've always been a fan of the Antec Sonata series, quality and classy. Get a QUALITY power supply. If there's one component to overspend on, this is it. I've seen far too many name brand PCs come in for repair with components torched by low grade PSUs.
Cheers,
-Kanati