Look at the following websites (click on links)
Kent sheds project
About Groundwork, the charity doing the organising
The Live It Well leaflet on Kent Sheds, which you can download
The Mens' Sheds Association website
You'll see on further reading that though the project is primarily aimed at older men, some projects also welcome like-minded female members and younger lads.
You can also see the Kent Sheds leaflet below.