places for bitcoin:
https://localbitcoins.com/ - like craigslist but just for exchanging bitcoins. can be fast, can do paypal and other stuff to pay.
https://www.mtgox.com/ - located in japan. highest price. ~impossible to get cash out. need to verify id. equal volume with bitstamp (~31%)
https://www.bitstamp.net/ - located in europe. harder to cash out in usd because it's in europe. lower price, lower fees (0.50%) on trades. need to verify with drivers license/proof of residence in order to deposit any cash or bitcoin. expect a week to be able to trade anything. equal volume with mt.gox (~31%)
https://coinbase.com/ - i plan to go through coinbase once i cash out. located in usa. easiest to cash out into bank (lowest fees/time)because it's in usa. higher price than bitstamp, but higher fees (1.00%) on trades. need to link with bank before you can buy or sell any bitcoins. expect up to 3 days to verify. not actually an exchange, and bitcoins/cash can take up to a week to acquire once bought/sold - but the price you bought at stays. used by reddit and okcupid to handle bitcoin payments.
https://btc-e.com/ - russia, i wouldn't trade here unless for litecoin. 25% of market volume for bitcoin

higher price generally means that it's harder/takes more time to cash out in dollars from that exchange.

places for litecoin:
https://btc-e.com/exchange/ltc_usd - located in russia. 

idk any more for litecoin