How can I change encoding options in LAME?

Disclaimer - I am not a LAME user.

But having said that I can offer some advice. I take it you are using LAME from the command line (if you are using a GUI I can't help you). If so try lame -help or lame --help (depends on which convention they use). In general this works for all Unix command line apps. If that still does not do the trick try man lame. If I do this on the encoder I use (on Linux) I get all the options I could ever want.

From a google search (lame command line options):
in constant bit rate mode -b x sets the bit rate to x.

Stereo modes:
-m m mono
-m s stereo
-m j joint stereo
-m f forced mid/side stereo
-m d dual (independent) channels
-m i intensity stereo
-m a auto

Hope that helps.

I have used LAME for a while now and could help you if you use the iTunes Script that allows you to encode with LAME.

It makes the process much easier.

You can change the settings inside the AppleScript and then pick the songs you want to encode from iTunes.

Hope this helps