This is a quick how to post to install Arabic language on MOSS 2007 installed on Windows Server 2008

Steps:

1. Download the language pack from here.
2. Download the SP1 form here.
3. Extract the language pack image to a folder, ex [C:\MOSS\Arabic support]
4. Extract the SP1 files to the same folder, by running the following command [officeserverlp2007sp1-kb936984-x86-fullfile-ar-sa.exe /extract:”C:\MOSS\Arabic support”]
5. This will display the update wizard, go with it, it will extract the files only
6. Go back again to the folder and run [setup.exe]
7. Finish the setup and it will run the MOSS configuration wizard.
8. After it finishes, you will find the Arabic language drop down list when you create site collections.

I hope that helped

Ahmed