There\'s not much more to my question than that. gem install mysql doesn\'t work and I haven\'t found anything by Googling.
When I try gem install
It looks like you still need to install MySQL's development libraries. These are required for the gem to build successfully on your system.
[Edit] Seems the RoR Wiki is no longer available. But, Ubuntu has offered their own walkthrough which suggests:
sudo apt-get install mysql-server mysql-client
sudo apt-get install libmysql-ruby libmysqlclient-dev
sudo gem install mysql
See http://wiki.rubyonrails.org/database-support/mysql#installation for more detail.
Example: Ubuntu
sudo apt-get install mysql-server mysql-server-5.0 libmysqlclient15off \
libmysqlclient15-dev mysql-client-5.0 mysql-common
sudo apt-get install libmysql++-dev
sudo gem install mysql