SAN ANTONIO (AP) -- Beginning next month, AT&T Inc. will raise the price of its most common broadband Internet services in many of the states where it operates, a company spokesman said Monday.The $5-per-month hike will apply in all but the states acquired with the buyout of BellSouth. It will affect customers who have the company's three slowest broadband tiers, ranging from 768 Kpbs to 3 Mbps, said AT&T spokesman Michael Coe.The 1.5-Mbps service is the most common among AT&T's 14.2 million broadband customers.The hike does not affect new customers who sign up for the slowest broadband service, Coe said.Customers …