When I read that Google has a free 411 phone service, I just had to give it a shot. It turned out for a beta, actually pretty good. The system is based off of it's local results database and maps, with a very cheery set of male and female voices. The number is 1-800-GOOG-41 1 and aptly responds similarly to the 411 operator - all except the fact that is it completely automated. No voice operators here!
Albeit, a bit strange calling a phone service provided by Google instead of an online service, as one expects from the search engine - it could prove quite useful and it's free.
The service is in beta and is called, Google Voice Local Search (GVLS), and according to Google, if the business is part of the Google Maps database, you should be able to get connected.
If there's only a single listing available, it offers to connect you; if more than one, you get a numbered list to choose from. And the best part is you can keep searching and trying other businesses to see how accurate the system is.