Google Inc. is expanding its Google Offers daily deal service into four new markets—Houston, Philadelphia, Miami and Austin, TX—bringing the number of markets in which it operates to 40.

But while Google continues to push its way into daily deals, the search giant recognizes that taking market share from leaders Groupon Inc. and LivingSocial isn’t easy. “Matching you with the deals that you want is our focus, but we can’t do it alone,” writes Ji Yang, a Google Offers software engineer, in a blog post.

That’s why Google is now aggregating deals from 11 more daily deal operators beyond the sites it already drew offers from, such as Gilt City, KGBdeals, and Plum District. Among the new sites are DailyDeals.com, APDailyDeals.com, Half Off Depot and Boston.com. The move will enable Google to expand the number of deals it offers consumers every day in 23 of its markets. “That’s a lot of deals! But don’t worry, we’ll only send you the best deals in your area, in one e-mail a day,” writes Yang.

More deals means Google will have a larger discount inventory that it can leverage to tailor offers to consumers’ interests. Google currently personalizes its offers by allowing consumers to take part in a “personalization quiz.” Consumers on www.google.com/offers can mark various boxes—for instance, Arts & culture, or Food & drink—to opt out of receiving discounts for those categories. In time, the search giant aims to also present deals to consumers based on what they’re doing—for instance, someone looking at a map of Palo Alto, CA, may see a deal for a restaurant in the area.

April Anderson, industry director, retail at Google, will speak at the Internet Retailer Conference & Exhibition 2012 in June, in a session entitled, “Paid search strategies for the smaller merchant.”