Below are "official" packages, but if you want to be on the bleeding edge (don't forget it ain't called "bleeding" for nothing), you can checkout for the SourceForge CVS (project = glscene), browse the CVS content here. If don't know how to setup CVS, please check the FAQ, do NOT bother downloading from CVS before you've read the FAQ (ie. do not download file by file!).
All GLScene files are hosted by SourceForge and can be found here:
Access to the user demos may be easier via the gallery
where a screenshot and description is shown for each demo.