Computers and computer programs are among the most wonderful tools available--as long as you know how to use them. If you don't, you quickly learn the true meaning of frustration. And let's face it: Most programs--despite what the blurb on the back of the box may say--are not cuddly. Which leaves lots of would-be computer users, especially businesspeople, floundering instead of working successfully. But if you're intimately familiar with one or more software packages, then you can transform the virtually flummoxed into virtual wizards (or at least computer-savvy souls) with a computer-training business. This is a hot field--according to the International Data Corporation, the worldwide market for technical computer training is nearing the $28 billion mark, with an annual average of $8,200 spent for information systems staff training and $3,000 per person spent on general staff training.