Use "Search by Content Type" dropdown box in Lexis-Nexis Academic, and choose Biographical Information search. Try also under a company's Hoovers Profile ("Search by Content Type" Company Profiles)
For additional info, use any one or more of these:
Business Insights: Global,
Business Source Complete,
Regional Business News, or
Wall Street Journal.
Seach individual executives' names as keywords to see if they've written anything, or been interviewed in the press
See the Investor Relations segment of the company’s website, or the latest annual report
Once you open an individual company's record, the auditor appears in the blue header, just under the address.