I guess it's about time I mentioned how to get stock data from Internet sites into an Excel spreadsheet. I usually use Yahoo.
In particular, I download historical Open, High, Low, Close and Volume from here.
There's an Adjusted Closing price as well which takes into account stock splits and dividends.

A spreadsheet which downloads this data for stocks on the Milan market is described here and another is here.
I tried (without a lot of success) to download from the India market here.

Having downloaded a bunch of data, you can make up your own Buy & Sell signals as described here.

You can even download the market capitalization, P/E ratio, 52-week low, earnings per share, etc. etc.. Check out this.

After downloading a bunch of stock data there are lots of neat things you can do, like:

• Looking to see if some earlier month was similar to the current month: click
• Seeing if you can predict the future: click  
• Looking for "sister stocks": click
• etc. etc.

>That's it?
What else can I say?

See:

• Download for 30 stocks.
• Download a web page.
• Download and plot the distribution of returns.

to continue