Shopping just got a lot easier, at least for some California residents.

Google today unveiled Shopping Express, which will provide unlimited, same-day delivery in the San Francisco area.

Participants will be able to shop online via national retailers like Target, Walgreens, Staples, American Eagle, and Toys R Us/Babies R Us, as well as local shops like San Francisco's Blue Bottle Coffee, the Bay Area's Palo Alto Toy & Sport, and Raley's Nob Hill Foods.

The experiment provides local delivery service "that we hope will make it possible for you to get the items you order online in the same day," product management director Tom Fallows wrote in a blog post. "So hopefully, no more trips across town for simple errands."

Google said Shopping Express will be available for "a low cost," but didn't specify an exact price. At this point, testers will get six months of free delivery.

"It's incredibly early days and so the service is only available to a small number of people in the Bay Area," Fallows wrote. That includes the city of San Francisco, and the Peninsula from San Mateo to San Jose

"The pilot will expand as we work out the kinks," Fallows said, "so please stay tuned."

Interested residents can sign up online to help test the new shopping initiative.

Users can select a delivery window from options like "Anytime Today" or a specific 3-4 hour windows, with specific instructions for Google's couriers.

News of the shopping service first emerged earlier this month with a report from TechCrunch, which said Google's service will cost about $10-15 less than Amazon's Prime, which provides fast shipping and access to online videos for $79 per year.

Amazon has also toyed with home delivery services. Its AmazonFresh service delivers groceries to residents in the Seattle area. But AmazonTote, which provided delivery for a wider array of products in Seattle, was cancelled in early 2011.