Today, many children are saying bye-bye to Barbie and telling G.I. Joe to get lost in favor of more high-tech gadgets and playthings. Take for instance the tech-savvy Foster family of Boyds, which has five computers and digital organizers for each of the six children. Users can now try out albums before they buy them at Sentero.net. Registered patrons can listen to any of the site's 50,000 albums over a unique Internet radio feed that offers crystal clear sound and features mp3 music downloads. MOSCOW----Sentero.net, a site offering mp3 music downloads, recently launched a free music streaming service sure to appeal to all music lovers. Inventors promise the new service will redefine both Internet radio and music marketing on the internet.