Samples Help, Presentation Skills and Baker Communications all offer presentation skills training online (see References). The first two are free, and the latter offers web seminars for $99 each as of October 2010.
Presentation skills are an asset that go far beyond simply getting up and speaking on a topic in front of an audience. Skills training can teach you body language techniques, intonation, answering questions and objections, relating to your audience. You can even learn the ins and outs of using PowerPoint as well as various audio-visual equipment, such as projectors.
Typical employers looking for presentation skills include the sales industry as well as marketing and training companies. Basically any segment of business that uses the art of convincing people will benefit from your presentation skills.
Good presentation skills can lead to challenging and well-paying careers. For example, as of October 2010, the average salary for an expert public speaker in the United States was $70,000, according to Simply Hired.