You need to look at "Trade exchanges", not just "Exchanges".

Trade Exchange = To make offers (bid/ask) or (buy/sell) {You set the rate you desire, as an "order"}
Exchange = To get an exchange, at a specified exchange-rate that the exchange has offered.

Here are a few "Trade exchanges" and "Exchanges", otherwise known as "Markets"...
(Look under the markets menu on top.)

http://bitcoinwisdom.com/