Okay
Format that memory stick again before you start!!
The 1.50 and 3.03 sony updats are in the downloads section here...
http://www.digitalworldz.co.uk/forums/downloads.php?do=cat&id=61
Download them, unrar them and rename each EBOOT.PBP to 150.PBP for the 1.50 sony firmware and 303.PBP for the 3.03 sony firmware. Copy these two files to the oeupdatemaker folder on your computer. Follow so far; okay, next copy the oeupdatemaker folder and the oeupdatemaker% folder and the 303oeflasher and 303oeflasher% folders to your PSP/GAME on the memory stick.
Now on the psp go to the game menu and open memstick and you should see the oeupdatemaker program... run it. Once it has finished open the memstick on the computer again and navigate to the PSP/GAME/oeupdatemaker folder and you should see the DXAR file that you need. Copy this to the 303oeflasher directory on the PSP and then run the oeflasher. Gotta go now, good luck