Electronic Ballast Controllers

I am refitting two 20L double light hoods.  I have elected to go
with electronic ballasts to power 2 x F17T8 lamps in each hood. I've
been specifically looking at the GE/Motorola Electronic Dimmable
Ballast, G2-RN-T8-10C-120, priced at $83 at Graingers.  Does anyone
know of a cheaper source?  Does anyone know if there is a compatiable
controller that features a programable timer that would bring the
lights on at a set time at 10% and raise it to 100% in a settable
time duration and accomplish the reverse at another set time?  The
controller listing GE provided was useless and outdated.  I would
appreciate source(s) and costs if available.  Would it be advisable
to install a small equipment fan in the end of the hood to cool the

E. Keith Johnson
School of Graduate & Research Studies
East Tennessee State University @ Johnson City