You have to do following steps

1- setting ---->Modules----> Update

2- setting ---->Modules----> Update Module List

3- restart your computer or the server (log out then log in)

now you will found it if not retry steps 1 and 2

link for creat first module http://nicechirag.blogspot.in/2012/01/openerp-complete-guide-for-module.html

Finally i get my module working. Here is what I do:

• Check the value of addons_path in configuration file located at /etc/openerp/openerp-server.conf
• I get this value /usr/lib/pymodules/python2.7/openerp/addons
• Then, i put my module there.
• Update my module list
• My new module show up! :)

Thanks everyone!