The pre-compiled ffmpeg binary was downloaded from ffmpegmac.net. Place it into your ~/bin directory to make it available to you. Also make sure that your bin directory comes early in your PATH
export PATH=$HOME/bin:$PATH
Note that in general you should be cautious with installing binaries from the internet because you could easily catch malware this way.
[ICO]NameLast modifiedSizeDescription

[PARENTDIR]Parent Directory  -  
[   ]SnowLeopard_Lion_Mountain_Lion_26.02.2013.zip2013-03-07 11:53 5.0M 
[   ]ffmpeg2013-03-07 11:53 14M 

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