The development thread (including manual and support disk image) can be found here:
http://www.stardot.org.uk/forums/viewtopic.php?f=3&t=12150&start=420#p176865
Some demos (courtesy of simonm) showing off its capabilities can be seen here:
http://www.stardot.org.uk/forums/viewtopic.php?f=3&t=13545#p177181
The price is £52.50 including UK P&P. Overseas posting is usually £5 or so more. The package includes the board, fly lead, support ROM and 28-pin socket.
PM me or leave a reply in this thread if you are interested in buying some. I'll make another batch if there's enough demand

Cheers,
Rob