A media buy is the purchase of advertising space in a media venue. Print ads in newspapers, 30 second spots on prime-time television, banner ads on websites -- each can be considered a buy. Selecting your media buy should be an occasion for you to do some serious introspection on what it is you are selling, who you think your target customers are, and where you are likely to reach them for the lowest cost.
If you are a major player with a huge advertising budget, your media buy of first choice will be television, of course. The next step is finding the television shows that appeal to the same demographic as your product or product line, having your ad agency develop commercials that appeal to that demographic, and purchasing your time. Smaller businesses make their buy in the local newspaper or regional magazines, or perhaps on their local television stations. Media buys on websites are usually priced by thousands of impressions, or appearances, with a number of different advertisers rotating through the same space.
For the small business, there are a number of low cost media buy opportunities that you should consider before spending your entire advertising budget on newspaper ads:
Local cable: Your local cable company inserts ads throughout the day into both network and cable programming. When you are watching a prime-time show and see an ad for the local restaurant, that is time that is sold locally and only reaches your viewing area. Local cable time varies considerably in cost depending on the time of day, the show's ratings and how wide a distribution you wish to purchase, since some cable companies cover a wide area. Thirty seconds on Sci-fi Channel repeats in the wee hours of the morning might cost as little as three dollars; midday on the Oprah show, considerably more.
Independent Web comics: If you are targeting a younger demographic, consider making your media buy on an independent web comic. These comics update several times a week, are the sole property of the cartoonist, and often have a very wide readership among people in their twenties and thirties. Some web comics have tens or hundreds of thousands of views a day. Developing banner or tower ads that appeal to a particular comic's readership can be worth hundreds or thousands of hits to your website, and such a media buy might be priced far under what you would pay at a more commercial site.