MetaStock data is a propietary data format popularized by MetaStock technical analysis software.
Reuters provide very good and reliable EOD data in MetaStock format, and as a Sentient Trader user you can take advantage of a 30-day free trial period of this data. Refer to this tutorial for getting started with Reuters data.
Creating charts with MetaStock data in Sentient Trader is very simple. Take a look at this video which explains the process: