I just found this easy guide to get my Ubuntu to show up in the Network window in Finder on my Mac.

How to get your Linux-based AFP server to show up correctly in Leopard’s new Finder

My Linux server is running Ubuntu 10.10 and the steps I needed to get it working were slightly different, but generally easier since Netatalk seems to have come a long way since that blog post.

sudo -i
apt-get install netatalk
apt-get install avahi-daemon
cd /etc/avahi/services
wget http://www.disgruntled-dutch.com/media/afpd.service
service netatalk restart
service avahi-daemon restart

Worked for me

Apparently you can even use the new Netatalk as a server for Time Machine!

If you’re on an older version of Ubuntu then you might get an error after installing netatalk like this

Starting Netatalk services (this will take a while): nbp_rgstr: Connection timed out
Can't register cctv:Workstation@*

This can happen if you have any virtual network interfaces configured. The solution is to tell netatalk which interface to use. Just edit /etc/netatalk/atalkd.conf to do so and add the network interface on a line by itself. In my case I only want it to use eth0.

Unfortunately at this stage the system considers the netatalk installation to have failed. I found that in order to make aptitude happy, I had to do this:

apt-get remove netatalk
apt-get install netatalk

The remove instruction still leaves your edited /etc/netatalk/atalkd.conf in place which netatalk uses upon installation. Everything should work fine and aptitude should now stop moaning every time you use it.

Additionally you may want to disable AppleTalk, which (I think) only older Mac OS versions use.

ATALKD_RUN=no
PAPD_RUN=no

Then restart netatalk.