You need to set up Facebook App ID and your Fan Page URL to Simple Facebook Like Widget in your sidebar..
From this widget you get to choose how you want Facebook like box to be displayed on your page.
You can select to display Facebook Like us header, Show your Facebook fans or show the latest posts in your Facebook stream..
All you have to do is install this plugin, drag the widget to where you want to display it, change the options on the widget admin screen and thats it.
Sidebar front-end Facebook Like Plugin...
As this is WordPress Widget it's very easy to install..
Upload 'jw-fb-like-box zip to the wp-content plugins directory and unzip the file.
Activate the plugin through 'Plugins WordPress.
Go to Appearance -> widget screen drag the widget to sidebar and fill out the options...
Browse the code, check out SVN repository, or subscribe to the development log by RSS...
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