Webpages
www.[composerdujour or composer's selling agent].com may end up
being one of your sources of information, but be sure and look
elsewhere and check information with reliable sources!
Consider who is supplying the biographical information:
Are there quotes from reputable, tracable sources?
Or is the information all supplied by the composer?
What is the site promoting or selling? The composer and his/her works? Scores or recordings in general? Tickets to performances?