Isn't HP UX commercial? If it is, you won't find any (legal) free "simulator"/emulator for it..for the basic command line all-around skills you can use practically any Unix, including Linux (learn to use the shell first, use tsch and bash for a start). If you need to learn some HP UX specific stuff, then you probably need to get the real thing - pay for it, very probably.
If you can find HP UX simulator on the web, you can probably find Windows Vista simulator on the web as well - just as legally, just as probably, as sad as it sounds.
Last edited by b0uncer; 08-07-2008 at 12:10 PM.