Guess I seem to be joining this topic a bit late but glad to offer some insight on gay rowers and rowing in the UK, Canada, and the US... including Dallas.
Brian here - I run GLRF and our second largest membership by country is the UK. We have members from all over England. The biggest concentration seem to be in London but we have members in Leeds, Manchester, Nottingham, Cambridge, Oxford, Brighton, Norwich, Newcastle, ... such a long list. Our third largest membership by country is Canada, with most of our members residing in Vancouver and Toronto.
You should check out our new forums in our message board - tied to regions in a country. We may have gone overboard for the UK - we created 12. For Canada, we made 6. Naturally, Texas is considered its own region... Why is it that everything in Texas is big?
Dallas has a rowing club that is getting huge. They are or have moved to a new boathouse on a new lake and have boats galore. Their next learn to row class is in September: http://www.dallasrowingclub.org/cms/index.php?page=lear_to_row
We purposely structured GLRF to be an individual membership organization that respects each person's preference for their respective rowing club. So no, there aren't that many gay rowing clubs worldwide but there are soooooooo many gay and lesbian rowers out there, happily rowing. We just added our first member from Mexico, bringing our worldwide membership to 27 countries.
Yep, we welcome all members of the rowing community, rowers, coxies, coaches, and race officials.