What details from the PSU should I be comparing to my current components, and the GTX 660 Ti to make sure it's compatible? The SATA Power Connectors? The PCI-E Connectors? What?
It depends on the connectors your mainboard and other components/peripherals require. For example, say I have a computer with 2 SATA hard drives, a video card that requires an 8-pin and 6-pin PCIe connector, an IDE optical drive, and a 24-pin motherboard with 8-pin CPU connectors. I would need a power supply with at least 2 SATA power connectors, a 6+2-pin/8-pin and 6+2-pin/6-pin PCIe connector, a Molex connector, a 20+4-pin/24-pin connector, and an 8-pin/4+4-pin CPU power connector.
It's all really dependent on your setup. Any power supply (as long as it's decent quality) with sufficient connectors will do.