Are there any themes for Windows 2003?
I am primarily looking for official themes from Microsoft although I would not mind hearing about unofficial themes as well.
Officially, the only themes available to Server 2003 are the same as Windows XPs. Simply go into the Services Manager and start the "Themes" service, and set it to auto-run, or type this into a command prompt with administrative permissions:
sc config Themes start=auto
sc start Themes
Unofficially, there are plenty of ways people have managed to jack in new themes.
I don't recommend this part:
You can install your own themes from various websites, such as http://customize.org/xpthemes. XP's and Server 2003's shell are similar enough that XP themes might work in Server 2003 - or it might completely tank it. Try at your own risk.