is the most important part of your entire direct marketing campaign (let alone your business). If you cant easily and affordably contact a niche market, you shouldnt be marketing to it.   The key to finding the people in your niche market is to think about who else markets to the same niche and look to them to help you compile your list. It is very possible that they will rent their list to you or you could offer them a commission from every product or service that you sell as a result of using their list.   An Example of Finding Doctors   Suppose that you wanted to market to doctors in your city. You could just go to the yellow pages, but sending a letter or offer to their place of business may not get a very high response rate because it will usually go through an assistant who will screen out all non-business type mail.   Here are some ideas to get access to their home addresses:   Get an electronic copy of the yellow pages. These are sold in stores like CompUSA. Get the names of the doctors from the yellow pages and look them up in the white pages. You may be able to match their names and legal titles (example, Dr. John Davis or John Davis M.D.). This will be time consuming so you may want to get a high school student to help you.   Go to the Oxbridge Directory of Publications. This reference manual contains demographics information on over 20,000 magazines and newsletters. Youll be able to find publications that reach specific markets, which have the characteristics you want. For example, you might discover a magazine like "Physicians Lifestyle", a bi-monthly publication that reaches every single medical doctor in the country.   Go to your local library and browse through the Standard Rate and Data Service (SRDS) list directory. In it youll find just about every mailing list known to man. It is an invaluable tool for your niche marketing efforts. You will find lists of doctors that have purchased recently through direct mail.   Contact the organizations and associations that doctors belong to such as the American Medical Association or your state medical association. If the associations wont rent you a list then ask if you can get a list of magazines, journals and publications that cater to the medical community. Magazines are very good sources for renting lists.   Go to MediaFinder.com and search for media such as newsletters, magazines, journal, periodicals and other media that are targeted toward the medical community and doctors specifically. A couple of references I found at MediaFinder.com were the APPA Digest, which is the publication for the association on financial planning for doctors. Another media was the Allergy Hotline Newsletter, which is a newsletter for doctors and other medical