Here's a place I found doing a search for radiant floor heat:
Hydronic radiant heat - Systems, design, and installation resources
I DO NOT endorse them, as I have no experience with them. It's just an example. However, they do have what appears to be a design team available to help you.
I did install radiant heat in the upstairs and downstairs lavatories myself. Drilling the holes in the joists and threading the PEX was about the most difficult parts of the job. All parts for the job are available at any box store. Most definately worth the effort!