I've Vegas Pro 10 without the DVDA (computer was a gift).
I've finally found perfect settings in Vegas Pro which improves my PQ from my DV-AVI source that has PCM audio.
Problem is, Vegas doesn't render ac3 without the DVDA. (actually, it does but it's a studio pre-set at only 192kbps - looking for 384kbps)
How can I manually add ac3 to make a compliant mpeg for DVD authoring?
Is there a tutorial for this somewhere? I can't watch videos as I'm on a dial-up connection.
Thanks

Problem is, Vegas doesn't render ac3 without the DVDA. (actually, it does but it's a studio pre-set at only 192kbps - looking for 384kbps)

You have to use the Dolby Digital AC-3 Pro template and customize it to get 384.
Since you don't have DVDA though, this will probably not be available to you.
You didn't say but I assume that the previous owner transferred his/her Vegas license to you.
If that is the case, DVDA came with Pro 10 so you should be able to download and install it free of charge.
You will need the appropriate permission but that would have come with the license transfer.