If you are working on a shoestring budget and you want to get into direct mail without having to fork over thousands of dollars for a high quality list of names, then you need to keep reading. Here is a secret that you can use to find high quality names for your next direct mail campaign without paying a dime.
This trick will not work for every niche of course, but it will work for many. The theme is professional organizations. Many of these groups publish their member contact lists as a service to their members. Occasionally you need to purchase a membership to the group to have access to the member directory, but that can give you even more credibility, saying that you a member as well and that you have an exclusive offer. However, many of thee groups provide that addresses of businesses in a niche, managers, and many other categories just by searching for your particular group.
Government offices are great for this as well. Most agencies in cities, states, and on a national level will publish all of the officers realtor mailing list names and addresses. You will know exactly what they do for a living and where to mail them targeted information. You can do this with school districts, entire state governments, and different watchdog groups.
If you join a local chamber of commerce, one of the perks is a member directory. Again, you can market the fact that you are a local business as well and show how you can benefit them. The National Association or Realtors has a list of all registered realtors. You can also get that list by state. Just think of how powerful that list can be if you are selling a product or service for that niche. 
Finally, you can ask you local librarian for help. Larger libraries tend to subscribe to many catalogs that can contain lists of individuals in your niche. There is not free lunch here, of course, and you will have to spend the time to copy and type out all of the names on the list and into your mailing software, but at least you will own your own list after that. The most important part of direct mail is having a qualified list and then you need to have an excellent sales letter to close the sale on your targeted, tested product. If you can get all three of those parts in line, you will have a very high closing ratio compared to mailing to a paid list.
