If you are literally just getting started, the services offered by most major stockbrokers (information here) as a part of their trading account services will be a good place to start (and free). Firms such as Trade King, eTrade, Charles Schwab and Ameritrade provide a range of online tools. These will give you a feel for how portfolio management software works without having to pay extra to learn. However, these services typically offer no advice (known as execution only), which means that a separate service will be required for information analysis.
ECN/Level 2 quotes: ECNs, or electronic communication networks, are computer-based systems that display the best available bid and ask quotes from multiple market participants and then automatically match and execute orders. Level 2 is a subscription-based service that provides real-time access to the Nasdaq order book composed of price quotes from market makers registering every Nasdaq-listed and OTC Bulletin Board security. Together, they can give you a sense of orders being executed in real time.
You’ll come across an overwhelming amount of information as you screen potential business partners. But it’s easier to home in on the right stuff when wearing a “business buyer” hat. You want to know how this company operates, its place in the overall industry, its competitors, its long-term prospects and whether it brings something new to the portfolio of businesses you already own.