Conference Proceedings tend to be included in discipline specific journal databases. Check a particular subject guide, e.g. electrical engineering, for recomended journal databases.
In addition, the following databases cover all the sciences and include conference proceedings:
Snell Library also owns many conference proceedings in print. To find a print copy of a conference proceeding, search in Scholar OneSearch, the library's catalog. You should search by keyword for the name of the conference. You can't search by either the author(s) or the title of the particular paper.