Not sure of the size of your tank/fixture but if it is 48" long or less you might look into the Hagen GLO T5 HO kits. There is one model that will drive 2 @54w, and one for 2@24w or 2@39w. The come wired with power cord, ballast w/ switch, 4 endcaps pre wired, and clips. The ballast is a bit large but is designed to be mounted remotely in cabinet or other location rather than the fixture. I have had several of these for 2 years and have been very happy at <$50 per set. They can be found at many of the online aqua shops as well as on amazon.
http://www.amazon.com/Electronic-Bal.../dp/B0002AQLQA