Business advertising

The very first thing you need to know about writing and designing effective direct mail packages is that “you” probably should not. Effective copy writing and design is very difficult for the average person, and those that are good at it have done a lot of studying and have tested a multitude of approaches and styles depending on their understanding of the nature of their audiences. Don't expect a copywriter that is successful with "non-profit" solicitations to be equally as adept at writing copy for "for-profit" offerings. Both Picasso and DaVinci were masterful artists, "in their own right," with distinct styles, preferences, abilities and "audiences." Copywriters are like artists. People who are successful at creative are, in fact, practicing an art form.
The best way to find good, professional copy writers and graphic designers that can relate to your specific set of needs is to contact a direct marketing association office (i.e., DWAW is the Direct Marketing Association of Washington). There is one in every major city across the country. The people who work there are very familiar with the range of resources available to you. They can save you a lot of time in your quest to identify people who have a background of success in your interest area. This is not something that demands close physical proximity and you have a vast array of alternatives available to you. Finally, you definitely want to make "a previous record of success in your arena" a prime consideration in the process of identifying your "creative partner."
On the other hand, maybe you are a small business with limited funding and you want to give it a shot on your own without risking a lot of money. The best way to begin on your own is to look at the creative used by other entities like yours and essentially copy those things that (1) appeal to you and (2) you see on a repetitive basis. It is being repeated because it works! I don’t mean you should copy other material word for word, but by format and general content. You can also find lots of copy writing resources on the Internet (type the words “copy writing” into your browser and you’ll be amazed at how many resources you’ll find).
What you will quickly come to learn about creative is that testing is the name of the game when it comes to direct mail, and I would strongly suggest (in fact, insist!) it be done constantly to determine what creative will work best for a given offer or solicitation. If you are not testing alternative copy (among other things) in every one of your mailings, you are not taking advantage of the single biggest advantage that direct mail offers over other kinds of less targeted marketing types -- "measurability!" All of your mailings should be predicated on past results.