Although online services like CompuServe, Prodigy, America Online, GEnie and Delphi now offer their subscribers access to the Net, it's a mistake to assume that your Net-only marketing activities will reach them. Many of these services' subscribers spend most or all of their time in the service's own areas, not on the Net. Here are some reasons why you should include online services in your marketing plans.

• Every online service has business- and marketing-related discussion groups where you can get advice and make customer contacts. Try the small business forums on America Online or CompuServe, the PR/Marketing Forum on CompuServe, the Your Business BBS on Prodigy, or the Home/Small Business Roundtable on GEnie.

• Classified ads on online services are read by thousands. Ads on these services are actually classified into categories, which makes it much more likely that your ad will find an appropriate target than it will on ad-related discussion groups such as biz.misc or misc.entrepreneurs. America Online doesn't charge for classified ads. Prodigy charges $30 a month for a small ad, and CompuServe charges by the line and the week.

• Online services have far larger proportions of consumer-oriented users than the Net, and their median household incomes are higher.

• Information databases on CompuServe, Delphi, and GEnie in particular offer opinion poll results, trade names, manufacturers' registers, Dun & Bradstreet or Hoover's company profiles, and lots of other information that's harder or impossible to get on the Net.

It may cost you a few bucks a month for an account, but online services are rich with opportunities and information that should easily justify the expense.