If you get big enough to contemplate advertising in major newspapers or magazines or on radio or television, form your own in-house ad agency and save the usual 15 percent commission. This is as easy to do as printing up some letterhead with a name like XYZ Advertising Agency. Have a separate checking account if you're going to do a lot of this. This is standard procedure for medium-sized businesses who handle their own ad buys. The American Management Association has published a book by Herbert Holtje titled How to Be Your Own Advertising Agency, which may provide some useful hints for you.

Of course, if you can afford it, you can hire a professional ad agency and learn the ropes before plunging in on your own. Sometimes the money they save you in good media buys may make up for their commission. Look in your Yellow Pages and interview a few firms. The ad business is a very people-centered vocation so find someone with the kind of personality you'll be able to work with. They can also design and place infomercials if your product or service lends itself to this type of advertising. And don't forget the home shopping networks.