Title: "Strange Visitors"
Author: Roger Stern

Summary: (from the back of the book) THE METEOR HEALER — Spiritual guru Donald Jacobi announces that Smallville's glowing meteorites are the key to eternal health and cosmic strength. Setting up a Web site to sell the green rocks, Jacobi soon amasses a fortune...and a startling control over his desperate followers. Investigating these events, Clark unearths an ominous truth when he learns that fraud and dashed hopes are the least of the dangers the rocks pose for the townspeople. But can he find a way to stop Jacobi—before the transforming power of the meteors is spread around the world?