Desperately need help installing ffmpeg & mencoder


I’m using Joomla on one of my sites and I urgently need to get ffmpeg, mencoder and Flvtool2 installed; I’ve been following all the online instructions and nothing is working, the config commands are failing and I keep getting ‘no such file or directory’ the rest of the time.

Please can anybody help with this? I’m happy to pay someone as I really need to get this working - thanks!!