Challenging macroeconomic conditions are making life tough for office supplies retailers such as OfficeMax Inc. (NYSE:OMX), Office Depot Inc. (NYSE:ODP) and Staples Inc. (NASDAQ:SPLS) who are grappling with soft demand for big-ticket items such as business machines and other durable products. Recently, OfficeMax lowered its third-quarter 2011 sales outlook in the backdrop of sluggish back-to-school [...]