Where to download free blackberry bold 9000 theme?

Hey man, you have loads of them over here, the service seems nice: link

And about customization:
From your home screen, go to the last icon that says Applications and click on it. Now you should see a full page of icons. The first 5 icons in the top row will be what you see on your main home screen. While you are on this page of icons, if you press your menu button, you will see the option to Move Icon, just highlight the icon you want moved, then go to Move Icon and place it in the first 5 and you should be all set.
Source: link