You might want to try paramount orchids in Calgary. They are a breeder from the test tube stage and extremely knowledgeable. If you ever make it to Calgary you need to head to their massive greenhouses. (They sell to the public.) Anyhow, the website is
www.paramountorchids.com and their contact info is on the site. I'm pretty certain they would be able/willing to answer your questions. If you want an actual forum where you can interact with people I would try
http://www.aos.org/aos/MessageBoard/ Failing that there is a list of orchid discussion boards (many of which are in different languages) at
http://www.orchidwire.com/Forums/1/
Hope that helps you.
-Danny