Randy Heit has uploaded the long-awaited ZDoom 1.23b29 to the ZDoom file storage. This latest beta version will likely be the penultimate release before ZDoom 1.23 is officially complete and is available for win32 and linux, in both binary and source form. Randy has also posted the latest version of ACC, which is v1.18 and is also available as a source download. Some discussion on this beta is going on in the ZDoom forums here and here.
Update: ZDoom is now at 1.23b30. There are 2 win32 binary packages now, with one being a video logging build.