FreeNAS FFmpeg libmp3lame -- Need help

This isn't necessarily an issue with installing Serviio, but honestly I'm at my wit's end and don't know who else to ask. I've spent the last 6 hours trying to get libmp3lame support for ffmpeg because it is needed to limit a streaming bitrate with another program I am using on top of Serviio, which will allow me to stream music over Sprint's slow 3g network. I know that I have ffmpeg working because Serviio and this secondary program work, but getting libmp3lame support has been a whole different nightmare. Is there a simple way for me to enable it somewhere in a directory or config file? I managed to find the LAME .tar.gz file on the internet, and I extracted it to a directory on the NAS. Now I am left with a bunch of files that are useless to me because I'm (unfortunately) unfamiliar with command prompt and UNIX-based OS. I think I have to use ./configure somewhere, but once again, I'm very new to this. I apologize if this is an inappropriate place to ask this question, but like I said, I don't know anyone who could help. Thanks a lot.

[Cerberus]

http://wiki.serviio.org/doku.php?id=build_ffmpeg_linux

Thanks for the reply, Ceberus. I tried following some of those directions, but because of the differences between Ubuntu and FreeNAS, some of those commands don't work (apt-get, for example. Git doesn't work either, though I'm not sure if that's because I don't have something installed that I need). However, I was able to find the installed ffmpeg on my NAS. When I run it, I get this:

  Code:

ffmpeg version 0.7.11, Copyright (c) 2000-2011 the FFmpeg developers
  built on Feb  1 2012 12:10:53 with gcc 4.2.1 20070719  [FreeBSD]
  configuration: --prefix=/usr/local --mandir=/usr/local/man --enable-shared --enable-gpl --enable-postproc --enable-avfilter --enable-pthreads --enable-x11grab --enable-memalign-hack --enable-runtime-cpudetect --cc=cc --extra-cflags='-msse -I/usr/local/include/vorbis -I/usr/local/include' --extra-ldflags='-L/usr/local/lib ' --extra-libs=-pthread --disable-debug --disable-libaacplus --disable-indev=alsa --disable-outdev=alsa --disable-libopencore-amrnb --disable-libopencore-amrwb --disable-libcelt --disable-libdirac --disable-libfaac --enable-libfreetype --enable-frei0r --disable-libgsm --disable-libmp3lame --enable-libopencv --disable-libopenjpeg --disable-librtmp --enable-libschroedinger --disable-ffplay --disable-libspeex --enable-libtheora --disable-vaapi --disable-vdpau --disable-libvo-aacenc --disable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxvid
  libavutil    50. 43. 0 / 50. 43. 0
  libavcodec   52.123. 0 / 52.123. 0
  libavformat  52.111. 0 / 52.111. 0
  libavdevice  52.  5. 0 / 52.  5. 0
  libavfilter   1. 80. 0 /  1. 80. 0
  libswscale    0. 14. 1 /  0. 14. 1
  libpostproc  51.  2. 0 / 51.  2. 0


I saw the "--disable-libmp3lame" and attempted to enable it using various made up commands, but no luck. So i then copied the libmp3lame folder that was in the .tar.gz file I downloaded to /usr/local/include because I hoped it would register there once I restarted the server. That didn't work. The last thing I have done is looked into /usr/local/lib because that's another directory I saw when I ran ffmpeg. libmp3lame was already in there with several file extensions: .a, .la, .so, and .so.0. I have attempted to use ./configure in multiple directories, but each time I get a "command not found" error. Thanks again. I appreciate any additional help that you can offer.