The Mess Hall

Ok it's dead easy and free.
You can also create custom clips too.

Here's how:

first you need to setup itunes, done that? Most people probably have, so no setup import settings.
click edit, preferences.
Then import settings, set to AAC encoder and the bitrate you want, the higher the number, the better the qaulity. now you've done that, you need to create the new version of the file.
Right click on the file you want to convert, then click "Create AAC Version". It usually only takes a second or two to do this, but for big files... it will take longer.
Now you need to find the file you created.
Right click on the original file and select "show in explorer" (this part is for windows users, I don't know about other platforms). The file is usually the one post fixed with a number
in this case the number 1.

And thats it, now copy that file(s) to you android device.

Advanced: Custom Clips
Pretty much the same as the above post, but this time we set a start and stop time.

1. Right click on the files, now click Get Info 2. Go to the options tab now edit the start and stop time, and then click ok.
now create the AAC version as before, this time it will save only that clip.

Cool eh?

Or download the Android App on your phone,
And listen to the track etc and crop it to what you want