about coustomizing - new plant, st. location

hi

everybody

when i m going through spro for define new company , company code , plant, storage location

why im not able to do so

system shows me,only for display not for changes

also not giving " new entries "option in details

im using 4.6c

plz, anyone give me proper solution for this

so how can i create new co, co code, plant , storage locations