I'm assuming you want to do it into redbook audio format for playing in an audio cd player without mp3 format support, since a 120 minute mp3 from an audiobook should not be that big unless someone recorded it at a bitrate way too high for simple spoken word. If not, then the rest may not apply.
If you're doing it on audio cd's, then you'll need to convert it to wav's via Winamps diskwriter plugin. Open winamp, select diskwriter, then click configure below it. Tell it where to dump the wave file and leave everything else the way it is.
Play the mp3, and it'll take a minute or two to convert the mp3 to wav. You won't hear anything, but tbe progress bar on the winamp console will skip ahead in chunks every second or so until it's done.
Then, locate an older copy of cool edit that will allow you to trial it. Adobe recently purchased cool edit, and I do not thinkt they allow you to do a trial period anymore. Olderversion will limit you to two of the unique features, which you can pick on startup, so it should still work.
Select the wav and go to the 80 minute mark in the timecode section, which will be listed under the waveform window. Might want to do it at 75 minute just to be safe, or whatever minute rating the CD-R's you plan on using are rated at. Select everything to the right of that timeframe and go to the edit menu to select cut.
Save the wave file now as ebook1.wav or whatever name you want. Then select file menu, new and paste what you cut into the new wav. Save it as ebook2.wav. Use Nero, EZCD, or any other popular cd writing software to burn an audio cd with the wav's as the sources. They should be playable in any CD player at that point.
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