Just thought I would mention it, I recently found out about another company that makes environmental control systems for hydroponics. I have no idea what they cost or how well they work, but they are a large company (out of British Columbia Canada). They do have a (1-800) phone number and e-mail, as well as a physical address listed on the contact us page. I've been meaning to look into their systems, but haven't done so as of yet.
Argus Control Systems
P.S. I don't know if they mail it to anybody, but you can even order a free CD about there systems.