Chris Perruna is one of the better known stock trading bloggers out there. He is a part-time trader who primarily uses the CANSLIM method of trading and has gotten quite a bit of good press for his accurate calls. One of his most popular and definitely a very useful post is on position sizing and expectancy. Here he provides a post explaining position sizing along with some excellent and very useful spreadsheets that help you figure out risk management for your trading system.
Aside from picking individual stocks, Chris is also very adept at calling the market. Here is a chart with his recent calls along with a history of his recent posts calling out tops and bottoms. As you can tell he is an experienced market technician and has done a good job at helping his readers navigate the crazy markets that we have experienced the past couple of years.
In addition to his blog and his regular posts he also is active on twitter. If you are interested in the stock market, are already an active trader, and especially if you are an active CANSLIM trader you will find worthwhile content on his site. A definite must add to your RSS reader.