State Chambers of Commerce Page
A good search engine, such as the ones to your left, may be your best bet yet in finding places to contact.  Search on yoru state.  You might get too many hits, so you can narrow it down by entering the word "chamber" next to your state.  ie: Wyoming chamber
Business Letter Inquiries
Chamber of Commerce
Convention Centers
Dept of Tourism
Convention Centers
Literature & information
Souvenirs, Give away items
U.S. Government