You may want to set up alerts or RSS feeds on the following web sites:
AIP Conference Proceedings - New Volume Alerts, RSS feeds on a topic.
ACM Digital Library - Conference Proceedings (requires personal registration)
IEEE/IET Conference Proceedings (requires personal registration)
You will receive e-mail alerts or an RSS feed as new conference proceedings are added to the web sites.
The following Series of Conference Proceedings are available in FULL-TEXT.
AIP Conference Proceedings (physics)
ACM Digital Library (Conference Proceedings) computer science
IEEE/IET Conference Proceedings and Standards
American Chemical Society Symposia Series (print copies)
Materials Research Society Symposia Proceedings (print copies)
Royal Society of Chemistry congresses series (print copies)