I don't know what to tell you about finding cheaper fixtures, but I
learned a long time ago not to just use cold white fluorescnet bulbs.
This is an old trick, apparently learned in drafting offices in the 50s
and since forgotten. My father taught me to put a cold white and a warm
white bulb in every dual bulb fixture, for much closer to natural light
color. Warm white is sometimes hard to find, though GE has just
introduced a "daylight" bulb that is very similar and does a good job.
Cold white bulbs are the cheapest and most efficient, which is why you
see them in the majority of fixtures. But they are not the only
fluorescent bulb available.