If you really want to write without a click track, some sequencers offer a way around the problem.
1. You play your part in freetime.
2. You then enter a special mode which allows you to \'mark as hitpoints\' any notes in your performance which you feel should fall on downbeats, or particular beats in a particular bar.
3. With this information the sequencer can now comform to your tempo flow, and if you\'ve selected enough hitpoints you can quantize other parts to very closely follow your free flowing performance.
Once you\'ve told the sequencer where all the hitpoints are you can copy the track (so that you keep your original unquantized part) and quantize the s**t out of it so that it looks good on the notation page.
When you listen, you listen to your unquantized part. When you look - you look at the quantized score.