If you're looking for dead center of the US, here's a few in Nebraska - http://www.datacentermap.com/usa/nebraska/omaha/
I've personally used both the CoSentry Omaha dn the CoSentry Midlands facilities before. The Midlands facility is one of the very few datacenters that operate with a 6 nines performance (99.9999%). I've never had ANY issues at their location.
If you're going for Texas area, Softlayer and CoLo4Dallas are two that I've used and continue to use.