there is something on the Russian forum, and a very useful link for these resources is this page:
These themes are very nice in that they also introduce and use additional applications, including one (history.app) to modify the list of last open books - at least this is the theory, I haven't tried it out yet.
The versions for 60X models are easier to donwload, but to get those by EdHell for the 90X models it took me ages, so I am uploading them here. The attached zip file contains the following:
The first file contains the various sources, while the other three contain the compiled themes and the applications.
I am working on adapting the themes for the 360, but it does take time and patience, so if you get anything done, please do update us
EDIT: it must be me, however none of the above work on mty PB903