EDIT:
Hey guys, since I'm now working on the official graphics for DF, I'm no longer maintaining this tileset. However, the magnificent Fricy has a repository where he uploads updates prepared by himself (and, I assume, using some graphics from the community).
You can find it here:
https://github.com/DFgraphics/Mayday/releases

Original info:
The Mayday tileset pack is here:

http://goblinart.pl/vg-eng/df.php

I'm preparing to move to TwbT and such, please use Truetype if possible to avoid garbled text.
I think the up/down keys are /* right now... list scrolling by <>.

This is the new URL, by the way, and it's here to stay (I've placed the site on my portfolio website).
Also, the blog will contain updates on new releases, if you want a convenient notification, you can use the RSS (links in the sidebar). I hope those work- again, let me know if they don't work for you.

If you have any troubles or questions, please read the FAQ (located on the main page) and then post them in this thread.
I will not be answering questions that are already answered in the FAQ.

There is a high possibility that I forget to include something in a release. If that happens, ask around on the forums- if others confirm that this is indeed a DFG bug, be sure to send me an e-mail about it (unless I will have also responded in the forums).