My personal Opinion.
If its chill enough to have your plants in the window then I would either go plant them outside or get them on a full indoor system. You could get a half decent system going for 2-300 bucks. Yes if you are going to by bulbs go to 1000bulbs.com and get them there. You wont find anything over 25w or 100w depending how you look at it at the Home Improvement store. If you have a specialty lighting store near by then you could go there. Also Daylight or 6500k lights are better then the Bright White 5000k bulbs. Check out some threads and you will get a good idea. Floodlight is good too just lots of heat. but wont burn your plants as long as you supply proper ventilation.
Good Luck Man