TMDHosting offers a great automated installer, which can be used with cPanel.

To perform an automated Joomla 1.5 installation you should open your cPanel and scroll down to the Fantastico De Luxe icon:

In Fantastico, you will find Joomla 1.5 in the Content Management section.

When in the Joomla 1.5 section, select the New Installation link as shown in this picture:

On the new page, you will need to fill in some details:

Install on domain: This will automatically show your domain name

Install in directory: If this is your first Joomla installation, it is best to leave this blank

Admin access data: here are your administrative username and password for Joomla

Base configuration: your e-mail address, name and the name of your site.

Then, click on the install button, which will take you to the next step:

Here a new screen informs you of a successful installation. Click the button and proceed to the next step:

This is very important. This page provides you with the URL to your new website and the administrative area for it. Bookmark them.