Here is a collection of resources you will want to use when trading futures and options. Beside these, you’ll find more useful sites in my instrument specific trading guides.
http://www.barchart.com/commodityfutures/All – This site shows the term structure for futures contracts live! Doesn’t have charts though for you visual people, but hey. Be creative, chart it in your head.
http://vixcentral.com/ – Real time term structure analysis of the VIX, to give you an idea of what the general market is expecting for future months.
http://www.cboe.com/micro/volatility/introduction.aspx – You would be surprised at how many volatility indices the CBOE maintains. Life isn’t just about the VIX you know.
https://research.stlouisfed.org/fred2/releases – Find market data on anything you can think of, going back decades.
http://cotbase.com/ – Commitment of interest reports on all types of futures contracts.