Google Inc., which helped popularize the idea of automated advertising sales on the Internet, has been quietly turning to an old-fashioned tool — phone calls — to compete in the hot market for local business advertising. The Internet search giant this year has hired several hundred sales representatives to call U.S. businesses such as spas, restaurants and hotels to promote new advertising initiatives, The Wall Street Journal reported. Because 20 percent of searches done on Google are for local information, “a strong Web presence can help neighborhood businesses answer those searches and bring in more customers,” said Marissa Mayer, Google’s vice president of geographic and local services, in a prepared statement.