you really can't make $50 trades and have a chance to make money. Absolutely lowest commissions will be $5/trade. In and out will cost you 20%.
I use Fidelity ($8/trade) and like the site very much. There are cheaper ones out there, but they won't offer research, yield tracking, etc.
Nothing wrong with you getting your feet wet and learning about investing. Just know the odds are stacked against you in a big way. There are thousands of people paid big bucks using big computers to find the deals. If you think you can beat them all, go for it.
And yes, you can do it. I've beat the market consistently for the last 10 years, but that will probably result in me becoming overconfident and getting wiped out this year