Dworkin hosts the primary distribution site for DGD himself. Both the source code (with patches up to the current version of 1.2p2) and binary releases (for selected architectures) of the stable development branch of DGD can be found at the site.
This site also provides patches for the experimental releases. These experimental releases are (by definition) not guaranteed to be stable but contain developmental code which will eventually become the next stable release (likely DGD 1.3).
In terms of bug fixes the following table indicates the correspondence between the experimental and stable branches.
Note that the contents of the README file on lysator are outdated, the main site is now ftp.dworkin.nl, not ftp.imaginary.com.