The "about" section of their home page says:
"Marketiva is a financial services corporation specialized in providing traders with high quality online trading services. With a team of dedicated financial specialists and technical support personnel, Marketiva operates globally as a market maker and principal counterparty to retail traders. ... ."My friend told me this marketiva gives the investor 5 dollars to start, closes your position automatically if you loose more then 1%.
There are other sites for trading financial instruments, like http://forex.com, but as he says, marketiva is a good to start because it is the one who protects most the investors. The others, as he said, are "spanking cats" ;-)