It is still somewhat difficult to sell bitcoins quickly. Many of the Bitcoin exchanges have had their bank accounts closed or have run into other regulatory issues. Others were not run that well and closed because of poor business practices. There are also systems that connect bitcoin exchangers locally. However, this may mean meeting a stranger to do a (possibly illegal) transaction so this could be risky or even dangerous. However, some local clubs are not forming that meeting in public places to exchange bitcoins and discuss bitcoin issues.
Most business that do operate exchanges require verifications that can be lengthy. if you think you may wish to trade in Bitcoins in the future it may be good to start the verification process as soon as possible.
The market is changing so rapidly it is difficult to point to any definitive list of exchanges.
http://millybitcoin.com/how-can-i-sell-bitcoins/
