0000899171-07-000024 4 1 20070517 20070518 20070518 CDW CORP 0000899171 5961 363310735 IL 1231 200 N MILWAUKEE AVE VERNON HILLS IL 60061 8474656000 200 N MILWAUKEE AVE VERNON HILLS IL 60061 CDW COMPUTER CENTERS INC 19930322 HARCZAK HARRY J JR 0001215333 4 34 000-21796 07863752 436 FARRINGTON DR LINCOLNSHIRE IL 60069 8474656000 4 1 edgar.xml PRIMARY DOCUMENT