I'll try to hit everything...http://www.proteron.com/n2mp3pro/
n2mp3 might be what you are looking for. It has a variety of encoders and works quite well in both OS9 and OSX.
There is also a script available from:http://www.malcolmadams.com/itunes/scrx/ituneslame.sit
That enables iTunes to use the LAME encoder instead of it's default. Since the LAME encoder is produced as a command line app open sourced the latest version is immediatly available to you in this way. You don't need to wait for any companies to update their software to work.
I suggest you check out the rest of the scripts at:http://www.malcolmadams.com/itunes/scrxcont.shtml
Because they allow you to do a huge variety of things some of which might become invaluable to you like the, "File Renamer" and "Add text to the end of the title" scripts have become for me.
Hope some of this helps. The only thing I never liked about iTunes is that it gives you no control over what the actual files are named. Using scripts you can get more control than you need.