Finding conference papers on the Internet can be difficult, so it's always nice when a new tool comes along. Microsoft have recently produced a search service called Windows Live Academic which seems to work in much the same way as Google Scholar - i.e. it allows you to search the Internet for the more scholarly material that is out there. However it has the added benefit of a conference filter allowing you to limit your search to conference papers. To give it a try, go to:
Other useful sources for easy conference paper searching are Zetoc (http://zetoc.mimas.ac.uk) and Scirus (http://www.scirus.com).