I f you feel that Apple is charging too much to upgrade from OS X 10.1 to Jaguar, take heart. Amazon is giving a $50 rebate on Appleis next iteration of OS X. The rebate is part of an Amazon back-to-school promotion, School of Rebates. Along with Jaguar, youill find rebates and savings on products such as FileMaker Pro, Office v.X, Toast with Jam, CorelDRAW, Acrobat 5 and Bryce 3D. Check it out at Amazon.com.