sorry 4 newbness - how do you end a track that has a volume envelope? If I drag envelope to bottom it still continues forever
lol - I'm doing a 15 minute vocal track for instructional cd & after I export it's 2 hrs

one of Sonar's quirks... do CTL+A to select all (or just select the track), then drag the cursor on the timeline from the end of track to the beginning.

There are a couple of ways to overcome this.
 
Hit ctrl + End - this will take you to the very end of your project.  From there you should be able to see the volume envelope complete with the final node. Right click the node and delete it. You might have to switch on Automation Lanes to make it visible, or rather, "non ghosted"
 
When you export, start by selecting the track(s) you want to be included, then sweep/drag in the timeline to highlight the range to be included in the export. Only then, click File > Export

thanks guys - I did find node

PS - Bristol....u answered on similar to this before when I was lookin 4 answer :)