[tex-live] tlmgr cannot install packages

[Karl Berry]

    I installed the minimal edition of TeXLive 2008 from the net in
    Ubuntu 8.10.

>From what you wrote, it seems you installed it as root.  I suggest
removing the present installation and redoing it, this time running as
yourself (no sudo or root).  Then you can also run tlmgr as yourself.

    If the same is required by tlmgr, 

tlmgr does not require special privileges.

    why is it not recognized by sudo?

Because when you run sudo, you get a different PATH, that (evidently)
doesn't include the texlive/2008 directory.  To fix that, you're going
to have read up on sudo, bash initialization files, etc., etc.  I can't
give you a simple recipe, sorry.

    Why would tlmgr want to download the package at a created temp
    directory where it has no access (me either?).

tlmgr isn't telepathic.  It assumes that the directory it was installed
into is writable.  There's nothing else it can do.

Best,
Karl