With the busiest shopping season just days away, Google is adding a tool designed to make it easier for consumers to map out their local trips to the mall.

The feature will be unveiled Tuesday at Google's Froogle shopping site. It will pinpoint the merchants selling a specific item within a designated ZIP code. Besides displaying a map showing all the local stores carrying the merchandise, Froogle also will list price differences.

Google is depending on a contractor to pull the inventory information from several hundred major merchants. Eventually Google hopes merchants stores will submit their own customized merchandise list to the newly created "Google Base".

Other major shopping comparison sites also have been upgrading in a bid to lure more traffic. Yahoo recently expanded its shopping site so it spans 90 million products, up from 60 million a year ago.