Maybe your version of LWP is too old. From its "Changes" file: 

2001-05-05   Gisle Aas <gisle@ActiveState.com>

    Release 5.53_94

    (...)
       - new convenience methods: get/head/post/put

[download]

What does perl -MLWP -le "print LWP->Version" say?

In reply to Re: Can't locate object method "get" via package "LWP::UserAgent" by almut
in thread Can't locate object method "get" via package "LWP::UserAgent" by Plankton

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