Before trying to install anything, you should try the following from the command line:

perl -MLWP::UserAgent -e 'print "Good!\n"'

In Ubuntu, there is a version of Perl tightly bound to the OS, and it includes LWP::UserAgent. I'm not certain why, but I believe it is part of the package management system.

One of the side effects of this is that Ubuntu can be a pain if you need to install modules - before invoking CPAN, I highly recommend you check in apt/aptitude/package management to see if there's an official distribution version of the package you want to install. In order to avoid some real frustrations when there isn't an official distro, I either use a local, user-specific copy of perl or at least local module installs so I don't have to deal with packages installed from multiple sources.

Update: This thread from the Ubuntu forum seems on-topic.

In reply to Re: LWP::UserAgent @ Ubuntu 8.04 64-Bit by kennethk
in thread LWP::UserAgent @ Ubuntu 8.04 64-Bit by timb

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.