Try the SEC's EDGAR or the websites of individual states' secretaries of state. Coordinated Legal maintains a page of links to these state offices.

You might also try Nexis Uni: Go into advanced search, click 'select a specific content type' and then 'SEC filings' under the 'Company and Financials' heading. From there you can enter your keyword and search.

From there you can click 'Location' on the left side and select whatever state you're looking for.