Most data centers are not going to be ideal for hosting unless you can find a Tier I or Tier II low-end one.
The vast majority of data centers are Tier III - with generators, UPSes, active cooling, fire-protection, early smoke detection (VESDA) etc. That means they have a PUE factor of 1.4+ (e.g. They have an overhead of at least 40%, and thats for a pretty efficient one). Your going to have to pay for all of that.
Its been awhile, but a couple of years ago, if you could get a $150/KW/month rate for data center space you were doing pretty good. And that was for the big boys needing 10,000 sq ft+ of space (e.g. Wholesale space). For a part of a rack, your likely going to be more like $450/KW/month.
Miners also qualify as "High Density" data center loads. The typical commercial data center is designed to handle 2-4KW/Rack. They may, however, have small High Density areas that are provided with more power and cooling - at a premium. On the flipside, if they have a shared-rack concept (many require you to buy at least an entire rack), you MIGHT be able to cut a bit of deal since you could help balance them out. Maybe. For a smaller data center. The big boys are not going to want to bother with you.
Last but not least: Many data centers will laugh and send you packing when you mention wanted to do mining. Over the years they have been burned repeatedly by miners abandoning gear (and not paying their bills) once the equipment ceases to be profitable. I've personally seen rows of S1s? (the GPU ones) sitting idle with the owners asking me if they had any value in S7 days.
All that said, Raymond posted a good link for you to start research at:
https://bitcointalk.org/index.php?topic=622998.0 Many of those appear to be asking more like $65/KW/Month, so I'm guessing they are lower Tier facilities (which is fine for your needs).
