Wal-Mart Stores' (WMT) aggressive ad campaign touting its low prices has competitors crying foul with state attorneys general. Eectronics retailer Best Buy (BBY) complained to the Florida attorney general's office, while Toys "R" Us raised the issue with authorities in Michigan, according to the Wall Street Journal. The paper, citing documents it reviewed, said the rivals claim Wal-Mart's advertisements make misleading comparisons or promotes