Becoming your own trading coach can be a daunting challenge, but there's no reason to go it alone. Here are some online resources that might be of help to you in extending your edge as a trader:
Vertical Solutions: creative market ideas and resources for testing trading ideas.
Daily Speculations: a range of insights about trading, markets, and life from Victor Niederhoffer and Laurel Kenner.
Quantifiable Edges: offers tested trading ideas in blog and newsletter, including a tracking of (very solid) performance.
Market Tells: loads of market data and indicators, tested trading patterns, and an excellent trend-catcher system.
SentimenTrader: tested market patterns, sentiment analyses, and insightful commentary.
Trading Success: Ray Barros is a coach and experienced trader who offers plenty of resources for traders to mentor themsleves.
Twitter Trader: My Twitter service that posts to the TraderFeed blog (or to you directly if you subscribe; it's free), highlighting trading themes, news, and updated market indicators.
If you know of free or commercial services that are unusually helpful in aiding traders' growth and development, feel free to post in the comments section. I have found the above resources to be especially fertile sources of inspirations and insights.