need advice on getting backtest data

Hi to all,

I am new to Trade2Win, and would like some advice.

I am trying to build a market indicator system. I am a stockcharts.com user and have found an indicator useful, the percent of stocks above the 200day moving average for the sp500 index, but it only goes back to 2002. Where can i find such data that will go back, at least to 1980?

I prefer to go online, without having to download software, but will if necessary.

Thanks in Advance for any help,
Joel