reading mp3 header

I am trying to find out the bitrate of an mp3 file.
I have successfully been able to retrieve other information (name, artist, title, year etc...) but not the bitrate of an mp3 file.

how would I go about doing this?

How did you retrieve the other info.
If you tell us how perhaps we can help, but I don't really know how to get mp3 info

the other info was retrieved by seeking 128 bytes from the file and then string parsing
FileStream theFileStream = new FileStream(@"Path\file.mp3", FileMode.Open);
Byte[] theByteBuff = new Byte[128];

theFileStream.Seek(-128, SeekOrigin.End);
theFileStream.Read(theByteBuff, 0, 128);
theFileStream.Close();
System.Text.ASCIIEncoding theEncoding = new System.Text.ASCIIEncoding();
string theTagInfo = theEncoding.GetString(theByteBuff);
if (theTagInfo.Contains("TAG"))
{

string theTitle = theTagInfo.Substring(3, 30).Trim();

string theArtist = theTagInfo.Substring(33, 30).Trim();
string theAlbum = theTagInfo.Substring(63, 30).Trim();
string theYear = theTagInfo.Substring(93, 30).Trim();

}


trust me, its not there (bitrate)

Here is the information about the file format. It should give you enough information to get started on what you should be reading:

http://www.dv.co.yu/mpgscript/mpeghdr.htm

However, if you only sample one frame of data, your #s might not be correct because of the ability of MP3 files to have a variable bitrate.