Yes, a simple 5000k home depot light will work fine for algae. I wouldn't spend hundreds on a fixture for the refugium, unless you intend to put corals in there from time to time.
As for the camera, I had a lot of luck with a P&S underwater camera- much cheaper than a dslr and you can also use it when you scuba/snorkel on vacation.
I use a canon d10, which seems to work just fine. They have made some advances with the latest models, but I'm not feeling the need to warrant the upgrade just yet.
Browse my PB folder for examples. Doug Kurceba's (GORILLA_MONSOON) Recent Uploads | Photobucket