Finding tempo in audio track

I'm sure there's an easier way but I ended up enabling the metromome during playback and adjust(found) the tempo where the clicks are closest to the audio. It becomes a problem for example with Steely Dan as they like to change tempo throughout a song. I tried audio snap with no success. I'm sure someone will have a better solution.

Hi, this a good way to do it from the reference guide:

Fit Improvisation


SONAR lets you record music from a MIDI controller without requiring that you use a fixed tempo. In fact, if you record without using a metronome, you are very likely to end up with a recording that does not fit onto a fixed tempo grid.

The Process > Fit Improvisation command lets you take a recording and create a tempo map (with measure and beat boundaries) that fits what you played. Your performance is not changed in any way, even though the note start times and durations are adjusted to fit the new tempo map. This is important if you later want to use any of SONAR’s editing features that depend on a proper tempo map for best results.

To use this command, you must record a reference track containing a single clip that matches your original track or tracks but has only a single note on each beat boundary. You should make sure that the reference track has one event for every single beat, with no extra beats or missing beats. The first beat of the reference track should be at 1:01:000. You can use any editing command to adjust the reference track.

If you want, you can use other types of events as markers on the reference track, such as a sustain pedal. Remember, however, that MIDI sustain pedals generate one event when the pedal is pressed and another when it is released. So if you want to use the sustain pedal for the reference track, keep this in mind. Click down, up, down, up, for one, two, three, four.

Remember that the better the quality of your reference track, the better job the Fit Improvisation command can do. You want each of your reference track events to be as close as possible to the beat of the music. Note that some keyboards transmit aftertouch events when you record your reference track. These extra events will prevent Process > Fit Improvisation from working properly. Therefore, you should delete these events before using this command, or filter them out when recording the reference track (using Edit > Preferences > MIDI - Playback and Recording).

To fit tempos to an improvisation

1. Record the reference track.

2. Select the reference track.

3. If necessary, combine all clips in the reference track into a single clip using the Track view
Clips > Bounce to Clip(s) command.

4. Choose Process > Fit Improvisation.

SONAR adds tempo changes as necessary to fit the tempo grid to the reference track. When you’re done, you should mute the reference track, since the reference track events are not rescaled.

Note: If the resulting tempo grid exceeds 250 beats per minute, you will see an error message.
If this happens, you can shorten the start times of each event using the Process > Length
command, decrease the tempo to compensate for the change, and then try again.

If you want to find the tempo. Put the sample in the trk. Double click the sample. It will show on the bottom in the loop editor. 

After seeing the tempo you will put the main tempo to the same value. You are ready to go now.