I ran into this company just having fun one day and would like to know what the members think of this highly rated Linux server OS? http://www.nitix.com/
I guess that's one way to pay to use Linux. You could of course just do an install yourself, learn what it takes to manage a Linux server, and then get it all free. Honestly, it's not that hard. All my servers are Linux and administered by me. It's extremely cheap and low maintenance.
If I really though I would need support I would go with http://www.suse.com/us/business/products/server/index.html And as Joel Naten said if you have a few skills there is no need to spend that amount or even any money on Linux.