i belive the one that noobtackulus made is 0.2 just look in his sig for the link
if it doesn't then just download iris 0.2 for the 1.0 psp and put the open it-put the iris folder on the root of your memory stick- put iris0.2 or whatever it is in your game 150 folder if your on custom firmware.
if your on 1.5 its the same thing exept download the 1.5 files and put iris on the root and iris2.0 or whatever and iris2.0% in your game folder..
just like any other homebrew
accept the iris folder goes on the root.