It depends on what are your needs .. Account Size/Trade Size ... How many trades do you place a year? Do you care if you want to trade Mutual Funds? Do you need advanced orders such TTO, Time Triggered, etc.? Do you want to place your trades overnight? Do you care if it is only web based or software based? Answering what you actually need can eliminate a lot of the brokers and narrowing the list. Try to narrow it to as low as two but no more than 5. When you come up with a list, it will be more focused and I will be willing to help and tell you about those "extra" fees some brokers charge? I have done an extensive study on most brokers in the US 
I am with MB Trading and Ameritrade. Both have been good to me but Ameritrade always lacks on giving me the best price when I place a trade with them. Margin Rate on Ameritrade is high too so I don't go on margin with them.
Here is a site with most brokers and their ratings:
http://www.elitetrader.com/br/
Another one that focuses on the main brokers in the US:
http://www.stockbrokerguide.com/usa_stockbrokers.php
Hope this helps!

I am with MB Trading and Ameritrade. Both have been good to me but Ameritrade always lacks on giving me the best price when I place a trade with them. Margin Rate on Ameritrade is high too so I don't go on margin with them.
Here is a site with most brokers and their ratings:
http://www.elitetrader.com/br/
Another one that focuses on the main brokers in the US:
http://www.stockbrokerguide.com/usa_stockbrokers.php
Hope this helps!
What a bargin