Hostgator.com

In my opinion Hostgator.com is the best host for Joomla and any other Open Source, LAMP based website script. They have the best Cpanel I have worked with. They have modern and fast servers, but above all, their support people are the best around. They are by and large helpful and caring of your issues. With hostgator you'll never hear "it must be your PHP script" whenever there is a server issue (something that usually happens at every other company). They are prompt and they never (well, rarely) talk to you like you are an idiot.