Hello,
I found a very good site which features the pronunciation of Russian names in a written format, and in sound files. The site also lists meanings and origins for each Russian name, so I definitely recommend you to check that site out! It might aid you in adding the pronunciations to the Russian names on your own site.
http://www.fredonia.edu/faculty/emeritus/edwinlawson/russiannames/
Sincerely,
Lucille