First of all it is important to find a niche in the market where there are a lot of like minded people willing to buy a certain product or certain category of products. Examples of these are motorcycle enthusiasts or solar power activists, etc. The most important is that there are a number of such people, which would constitute your market.
Moreover, you must choose your scale. Do you want to take your project worldwide or focus on your local area? For many people focusing on their local area will yield the best results because of your familiarity with the area and the ability to move and visit various businesses.
Once you have discovered your niche market you can then setup a professional looking website and populate it with content which is very interesting to these people. You are aiming here to create a one stop shop where your enthusiasts or activists would love to visit often and discuss on forums and be involved with your website as much as possible.
Your aim is to gather a certain amount of traffic per month. This traffic which you generate is very valuable and is definitely not just any visitors. These are people with specific demographic profile and specific interests or needs which you have discovered.
Now that you have this you can contact companies both online and offline which are selling products interesting to your market and offer them to list their name on your website directory in exchange for a certain amount of money per month. This is very interesting for these companies because they will receive extremely targeted traffic from you of people very interested in their products and ready to pay for them. It is a win-win situation.
Your job is then to keep populating your directory with such companies and making money from each company that you add to your directory.
And the people who visit your website would be pleased even more because all the resources such as interesting articles, discussion forums, etc as well as products from different suppliers would all be available on your website.
This is a very powerful way of making money online, which is also very stable and predictable, so you do not have to be afraid of monthly fluctuations or changing of rules or laws by which other methods are run. Moreover, you are in full control of every aspect of your business and you can replicate this method on another category or expand your current network to other countries or areas.
Once the business is running well you can also consider printing out directory books or brochures for circulation, creating price comparisons between the different suppliers that you have on your directory, offering discounts or special packages through successful negotiations with your members.
Very many paths are open to you at this stage, creativity being your only limitation.