This is a quick hack to install the 32-bit Ubuntu Wine package onto AMD-64 for Ubuntu releases older than Feisty. If you are using Feisty, this should no longer be necessary as amd64 packages are available in the APT repository: http://winehq.org/site/download-deb

Instructions:

First, you need to enable the Universe (community-supported) repositories in Ubuntu, then install several 32-bit libraries like ia32-libs and lib32asound2 (for using ALSA). You can install these with Synaptic, or from a terminal:

sudo apt-get install ia32-libs lib32asound2 

Then, download the Wine package by hand. You want the latest version available for either dapper, edgy, or feisty depending on which one you're using. New versions are released about twice a month.

Save the file to your desktop, and return to the terminal:

cd ~/Desktop 
sudo dpkg --force-architecture -i wine_*_i386.deb

You may have to edit the command to reflect the version number of the .deb you downloaded. You can delete the .deb file from your desktop when you're done.

Some advice for non_English locale feisty users: if you can't write not_english symbols in "wined windows" application try

sudo ln -s /usr/lib/locale /usr/lib32/ 

and restart application.