I wasnt able to get the download working either, on multiple mirrors. From the looks of it, the Darwine project has been abandoned, as there has been no news for over a year.
from the Wine FAQ:
3.2. I want to run Wine on an Intel Mac OS X (MacIntel) system, will it work?
(Also see the previous question.) As of March, 2006, simple applications are just beginning to to run on Intel Mac OS X. It's possible in about 6 months we'll see applications running similarly to how they do on Linux or FreeBSD.
There are some complicated issues surrounding Wine on Mac OS X. Working with low-level features, such as signal handling and system registers, are quite different on Mac OS X. Further hampering the issue are some bugs within the operating system. Beyond that, integration on Mac OS X becomes difficult because it is vastly different than a traditional *nix desktop. Menuing and graphics drivers are just two areas that require a complete reimplementation in order to be functional.
Good news, but its from march of 06, so its unclear of their current progress.
your best bet right now is to just buy a commercial emulator
http://www.codeweavers.com/