|Think about Loose Coupling|
Here are some more links with LWP info.. read this one and look at Planetscape's reply to my post with more online books.. Re: Perl code to check and count count if a word exists on a webpage.
Update: When you update a post, add some kind of tag like this so that we can tell that something new has been added. I would stay away from WWW::Mechanize::Firefox unless you really need it. This thing is pretty cool and I've done some experimentation with it, but this introduces another layer of complexity into the implementation.
(1) You are emulating a browser. You can claim to be different versions or types of browsers. I find it helpful to claim to be the "stupidest thing" that the website will allow. Many websites serve up different pages depending upon who you are claiming to be - dumber browsers get different pages than smarter browsers. Below I am claiming to be an ancient version of Netscape.
(2) Often it is not necessary to even parse what the server sends you. Below I just checked that I got a valid page (no 404 error or whatever), and then I immediately just post back my credentials. I know that this is the log-in page.
Of course as with all of these things, mileage varies.