ETFs
In the U.S., there are over 710 ETF sponsors. At the beginning of 2013, three companies controlled 84% of ETF assets (BlackRock, State Street, and Vanguard).
As of March 2013, there were ~1,500 ETFs, a 70% increase since 2008. Five online sites for ETF investors are: Morningstar.com, ETFDB.com, Indexuniverse.com, XTF.com, and ETF company sites such as BlackRock, State Street, and Vanguard.