If its external, you'll need
To fulfill the first requirement w/USB 2.0, I recommend this (the non-powered version; they also have a powered version that uses a wall wart, but unless you're using an inverter, this is useless to you). Both adapters support 2.5" (notebook drives) and 3.5" (desktop drives) drive connectors.
- a data connection, and
- a power connection
For power, you'll need a regulated +12v (and probably +5v...) for 3.5" drives, or +5v (I believe ATM) for a slimline (notebook) [C|DV]D drive or HDD (unsure of ampere/wattage requirements). Either tap the power in your computer for this, or come up w/another external supply. Oh, and you'll need ground, of course.
EDIT: just looked at the links to eBay that you posted. Yah, thats basically what you'll get from the link(s) I provided. Get whatever's cheaper. Keep in mind the power requirements.