I accidently used the app customize, to hide the icon for installer and customize. Now I can't use installer or fix it because I hid customize. Can I get to the app any way, or is there some way I have to reset it.
If you're comfortable with SSH / SCP and with editing plist files you can go in and fix it in M68AP.plist which is in CoreServices/Springboard.app/
Customize moves hidden things into the Special Array within the displayOrder Dictionary. You can just copy any paste them back into the main iconList Array.
Or alternatively - do a restore and start all over again.