Sight and sound are at the heart of new digital documents available online, and in the spirit of digital information's next phase, they carry a price tag. Internet retail giant Amazon.com, originally an online bookseller, is further expanding its product offerings with a new e-Documents section. Digital audio resources are being introduced by BeyondGuide, which wants to grab the ears of cell phone-carrying tourists, starting with those in the nation's capital. Amazon's e-Documents Store sells online texts from various sources that might be difficult to find in print. The list includes investor research reports, journal articles, reference material, magazine archives, and other research documents. "Right now, we are focused on market research with reports from IDC, Giga, Zona Research, those types of companies," says Kristen Schaefer Mariani, a spokeswoman for Amazon.com. "Visitors can also browse by primary subject: Business, Computers and Internet, and Science and Technology. What we are doing is aggregating a deep catalog featuring multiple publishers in one place." Amazon plans to add medical, education, and entertainment content in the months ahead. "It really is a limitless field," Mariani says. "Any printed document can be made into an e-document." Selections from the e-documents page can be downloaded for printing or reading as PDF or .LIT files, Mariani adds. The new offering is an offshoot of Amazon's e-Books page, which opened for business last November and now features thousands of digitized titles. While Amazon's online titles aim for the eyes, BeyondGuide is reaching for the ears of travelers equipped with wireless phones. The service provides an audio tour guide delivered through a cell phone, says Matthew Hoffman, BeyondGuide vice president for business strategy. "It's an experience that is completely different from what they would get from a tour book or from a WAP phone where they are browsing text." For example, tourists walking by Ford's Theater can listen to a re-enactment of President Lincoln's assassination. On the steps of the Lincoln Memorial, they can hear a recording of Martin Luther King Jr.'s "I Have a Dream" speech that was made on that same spot. At the National Gallery, they can listen to architect I.M. Pei explain the inspiration behind his design for the futuristic East Wing of the museum. The first BeyondGuide offering, which includes 15 hours of recorded audio, covers Washington, D.C. Callers can try a free demo or take advantage of a $10 introductory plan that allows access to the Washington guide for 48 hours. BeyondGuide plans to add New York by October along with San Francisco, Boston, and one European city this year. "You tell us where you are and we give you a choice as to what to listen to," says Hoffman. "We can personalize these offerings as you tell us more about yourself and we learn more about your interests." Features such as walking directions, real-time positioning, and restaurant referrals will be added by BeyondGuide as soon as the wireless carriers start providing location data. And in the new world of paying for content, Hoffman says, this is an example of useful information people will be willing to buy. "We have developed really highly produced content, premium level content that people will want to pay for," he says. "It's something that you can't really get anywhere else, especially if you are mobile."