Yeah, startup manager is removed from official repository of 12.04.
From StartUp-Manager is dead:
So, i have finally come to the decision to officially stop development
of this application.
For personal reasons, i have not kept up with Ubuntu much lately. I
was meaning to get back to this project someday, even said at one
point that there will be a SUM2. Sorry about that, i have realized now
that it will not happen.
The decision to make this announcement came today when reading a bug
report about some changes with the latest versions of grub. When
trying to figure out how to adapt to these changes, i came across
another app: Grub Customizer. After testing that app, i realized that
updating SUM would just be a duplication of work at this point. So
check that app out instead, it seems to work well. Of course, if
anyone feel like taking over this project anyway, just contact me.
Thanks all for using and contributing to StartUp-Manager in the past
Reading state information... Done Package startupmanager is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source
E: Package 'startupmanager' has no installation candidate
– siraj May 05 '12 at 10:18