No personal flying machines. No Dick Tracy watches. This fall's crop of tech gadgetry has more than gee whiz sizzle. They're about bringing tech advances into the mainstream. Just look at Apple's iPod digital music player, which has sold more than a million units since being introduced in late 2001. The player continues to gain momentum, both from consumers and tech critics. In one of the bigger pushes of the season, Hewlett-Packard plans to unveil some 168 digital imaging products this fall, such as a portable, thin, clear glass scanner or a device that easily allows the transfer of videotape recordings onto compact discs. These and other products in stores for the holidays "will allow anybody to do things that have been promised for a while but were limited to geeks," says Harold Sogard, general manager/partner of Omnicom Group's Goodby
, Silverstein & Partners, San Francisco, HP's agency.