An Aussie mag APC October 2009 [...] has a detailed article on this - using Ubuntu.

There is also a lot of info on the Ubuntu help forum on this. I had a go at setting some of this lot up but gave up - couldn't get Jack to work. It takes a lot of time and effort to get it working and it depends what you want to achieve as to whether it is worth it.

I don't think latency is a particular issue unless you are using the computer as a live mixing desk. The only thing I really wanted was the midi sequencer (Rosegarden or other) and I decided I could manage without. You need pulse audio and I have that disabled as audio does not work properly in Wine with pulse audio enabled. I have Noteworthy running in Wine and that is more important to me. Pulse audio also caused Kino, the video editor to go unstable.

Audacity works fine with my present Ubuntu setup, the audio players work and I can get midi playback. For now that's fine for me.