Mardi Gras is over, which means it’s time to plan for Jazz Fest. Internet users around the world already are. Dozens of posts to the music discussion Usenet newsgroups asking for 1996 Jazz Fest schedules appeared daily until the schedules were released. As soon as they were, Web sites and mailing lists made them public worldwide. The buzz over the 1996 New Orleans Jazz and Heritage Festival is one of the biggest and most wide-spread on the 'net—get ready for record crowds at the Fair Grounds....