Hi,
There are a couple of folks that let others know of their work in the ProgArchives board but, in general, this is such an independent and individual thing, that collaborations are almost a joke ... and no one knows or remembers Klaus Schulze even collaborating with an American for so many albums ... that were fun to listen to, but I'm not sure that there was a whole lot of depth in there, or detailed thought into putting the work together.
This is an area, that is sadly lacking ... and I think that most of it is that the 'system" and "ambience" is so song oriented, that it makes it difficult to find/see anyone that will fool around with the instruments, like our grandpa's used to in the 60's and 70's did with Cluster, Faust, Kraftwerk, Kluster, Heldon and so many others ... but nowadays, having fun playing something is not considered "music", and no one will even consider releasing it in America, which is sad ... there is talent in many avenues ... just not in America?