I can help you with that. The way that Wacom tablets identified themselves changed under Vista, and ArtRage required an update to correctly detect them. In your ArtRage program group you may have an item "ArtRage Updater". If you run this with ArtRage closed, you'll be able to download the latest update and apply it which will then allow you to start up ArtRage.
If the updater isn't in your specific version or you have any problems, not to worry, we also support downloading of the latest version from our site. Just go to our support page here www.ambientdesign.com/ar2support.html and click the top question ( about what to do if you've lost your installer ). That will take you to another page where you can enter your details and an email will automatically be sent to you right away with a download link you can use.
Once you've downloaded and saved the file from the link you can uninstall your current version and install the latest on your machine.
If you find you're having any difficulties, just send me an email to email@example.com and I'll be happy to work through it with you.