I've slowly been hunting down 'classic' giant maps that I somehow lost over the years.
As I collect them I'll be uploading them at utgmc.com under the download section.
There are still some UT map sites out there that host some of the maps but many hits lead to dead links.
I actually re-installed classic UT the other day and played a few minutes online but I quickly remembered why I uninstalled it so long ago.
Still and all, if you have maps that are zipped I can set you up with an account so you can upload them to the site for me.