DETROIT -- August sales at General Motors fell by 11-percent when compared to one year ago. The results were not surprising as in August of 2009 the federal governments "Cash For Clunkers" program was in full swing.  The automaker also reported a dip of seven-percent in sales when compared to July.  The Chevrolet division reported a sales drop of 22-percent over last year's numbers while sales at Buick, Cadillac and GMC were all higher.