I find MP3DirectCut to be the best way to create cue sheets (http://www.mpesch3.de/
It has a wonderful display showing the 'shape' of the audio without having to convert the mp3 to wav..
The interface is a little ... challenging.. but if you remember these few steps, it's great:
1. Listen to track (play/pause using space bar)
2. Pause when you reached the point that requires a cue (shift left arrow brings the cursor back a fraction)
3. On the keyboard type b n c ( no spaces, BNC are shortcuts for mp3directcut commands)
4. PLay to next cue and pause
5. type b n and c again to place the new cue..
6. Continue til you're done