I use the sites that Greencat suggested through his CD. Namely the following...
http://www.stockfetcher.com
http://www.stockcharts.com
Those are the two sites I use the most. I use the filters on stockfetcher and do research on those stocks at stockcharts.com.
To post a link of a chart, you simply use a site like stockcharts.com and look up the stock. Then you copy the link. After that, all you have to do is the following...
url="paste the url you copied here"]Name of stock goes here[/url
Just add closing brackets to the outside of it (like these [ and ]). Everything else should be self explanatory.