Between home depot and a decent garden center or farmers supply, you should be able to assemble a perfectly respectable grow room with the addition of just a HID light.
IMHO it's safer to walk into a grow shop and pay cash for a light than it is to buy one online, where your payment info and shipping addy are recorded. If you are sketchy about the grow shop, borrow your mom's car for the day (unless she has a grow at her house too lol).