iPhone owners scrambling to update to iOS 9.0.2 firmware before the signing window is closed by Apple may have had trouble finding the correct IPSW. These files are typically available from Apple's servers. Once a newer IPSW is available, links to the old version stop working.
While the correct IPSW file is still being signed by Apple, it must be downloaded from a third-party mirror. The release of iOS 9.1 renders the Pangu jailbreak tool for iOS 9.0.2 obsolete.
To find the correct iOS 9.0.2 IPSW file for your device, check here for a mirror where the iOS 9.0.2 IPSW files are still available. These download files include:9.0.2 [4S]: iPhone4,1_9.0.2_13A452_Restore.ipsw
9.0.2 [5 GSM]: iPhone5,1_9.0.2_13A452_Restore.ipsw
9.0.2 [5 GSM+CDMA]: iPhone5,2_9.0.2_13A452_Restore.ipsw
9.0.2 [5s GSM]: iPhone6,1_9.0.2_13A452_Restore.ipsw
9.0.2 [5s GSM+CDMA]: iPhone6,2_9.0.2_13A452_Restore.ipsw
9.0.2 [5c GSM]: iPhone5,3_9.0.2_13A452_Restore.ipsw
9.0.2 [5c GSM+CDMA]: iPhone5,4_9.0.2_13A452_Restore.ipsw
9.0.2 [6+]: iPhone7,1_9.0.2_13A452_Restore.ipsw
9.0.2 : iPhone7,2_9.0.2_13A452_Restore.ipsw
9.0.2 [6s]: iPhone8,1_9.0.2_13A452_Restore.ipsw
9.0.2 [6s+]: iPhone8,2_9.0.2_13A452_Restore.ipsw