Easy
I don't even trade that often due to swing trades and I have never been charged for data. I think the minimum commision is $30.00 and all the data is free... the data is $10.00 / month if you don't have that much commission spent on trades.
It's a block called Non-professional US securities and Commodities. It seems to include CME, CBOT, NYMEX, Stocks , Indices,,,etc. Everything I have ever wanted to see was available.