I've found this company to be the cheapest
http://www.petsupplyliquidator.com
and they still make a very good quality hood
you can get used hoods for 50% less though, so I'd recommend you get a used one instead.
I have a 24" 2x55w hood that easily fits a 10 gallon tank but can very easily be modified to fit my 36" 29 gallon also.
I just saw a 2x96w hood which I almost bought for sale on reefcentral.com
they have tons of classifieds postings on there. it was only 100$ and was 3 months old (to give you a price idea)
dont get fans they are useless!