How to install an init.d script in ubuntu?

How to install an init.d script in ubuntu?

i am trying to install an init.d script, to run celery for scheduling
tasks. Here is the steps i followed:
copied the file celeryd and pasted it in folder /etc/init.d/
created a configuration file celeryd in folder /etc/default/
now when i tried to start it by sudo /etc/init.d/celeryd, it throws error
sudo: /etc/init.d/celeryd: command not found
I googled about how to install init.d, i got this SO-question.
it says to issue a uname -a and when i does i get this:
Linux capsonesystem8-desktop 3.2.0-43-generic-pae
#68-Ubuntu SMP Wed May 15 03:55:10 UTC
2013 i686 i686 i386 GNU/Linux
and also it says use utils like "insserv" to enable this init.d script so
tried:
insserv /etc/init.d/celeryd but it throws error insserv: command not found
so i tried to install insserv sudo apt-get install insserv. but it say
aleady installed:
insserv is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 222 not upgraded.
So how to install init.d script?? Any help will be appreciated.