So there are a few questions about reading out there but none really properly answered it as to how one goes about taking a MP3 file of unknown characteristics and extracting the information about the bitrate(s) contained in the file, as well as how to find said frames in the file.
Some of the existing question which were similar in nature were answered with links to other websites that don't exists anymore. Or the content which was linked to no longer exists.
The closest I find is the technical documents over on http://www.mp3-tech.org/ with the guide for "MPEG Audio Layer I/II/III frame header" but then I also need to work around anything in the MP3 file which is not an audio frame so I seem to be needing information on locating that as well.