I can vouch for the Ridgid Sander. Had mine for years and never had any trouble with it. For intarsia work, you will need something with more finesse. Something like a Dremel or Flex sanding ball and a sanding mop. I know Judy Gale had a lot of information on her web site. http://www.intarsia.com.
At any rate, welcome to the village and the addiction.