A lot of people are making them themselves. It is a lot easier than making a steel bike since one of the big problems there is heat distortion. Since they are glued together, they don't have that problem and are much easier to get right.
Bamboo bikes is super awesome! You think they'd be all over the place by now.
"Hundreds of years from now it will not matter what my bank account was, the sort of house I lived in or the type of car I drove... But the world may be different because I did something so bafflingly crazy that it becomes a tourist destination"
Diego Footer on Permaculture Based Homesteads - from the Eat Your Dirt Summit