Did you know that you can direct your new fans to a specific landing page? Well you can! There are free applications that you can use. Here is the link for the Facebook Applications Directory: Facebook Applications-Click Here!
These are a few that you will be able to choose from:

As examples I will show you the difference between two of these applications. I used HTML + iframe + FBML = iwipa on one page and Pagemodo on the other. In my opinion Pagemodo was the simplest to create. However, HTML + iframe + FBML = iwipa offers YouTube videos and other media on your page.
HTML + iframe + FBML = iwipa:
Pagemodo:

Once you create your Welcome or About Landing Page, then you will have to update the Manage Permissions on your Fanpage.
Step 1:
When you are on your page click Edit Page.

Step 2: Follow the 3 steps shown

This Welcome Page will only be shown to new fans. Once they "Like" your page they will be directed to your Wall when visiting again. The Welcome tab will still be listed under your profile picture.
I really liked papemodo for mine. It was really quick, they walked you through every, and it was really customizeable.
In case we're already friends, here's the link straight to my welcome page: http://www.facebook.com/QuirkyCookery?sk=app_106171216118819 . I'll go back and tweak it later....I just wanted to put something together and see if it'd work, and it did.
Oh, and if you have any issues with it saying you have a premium option selected when you know you've only checked free stuff, go into your saved pages or account section. If there's a sample/example page listed, delete that...for some people, it tries counting that as a second page, which is a pay-for service.