Roger Elmer has a clever idea for a modern fantasy. Children inside the internet, moving about as they find links within a site and battling a villain with a PDF she uses to wipe out spiritual references—all make for an original story.
If you want an alternative to common youth series like The Babysitter's Club, this is a far better choice. If your child is ready for some easy-to-read, early chapter books along the lines of The Box Car Children, consider Digital Disaster. It is clean, with good values and family relationships. Some interesting bits of Christian history are introduced, like the noble orchestra playing "Nearer my God to Thee" as the Titanic sank and the work of Operation Mobilization's missionary ships. Some basic computer knowledge will be gleaned from the story. Since this first book in the series leaves the story unresolved, the reader may be wooed into continuing past the first book.
If, however, your children are not reluctant or beginning readers and are already accustomed to a different level of literature, be aware that the writing will not be mistaken for Dickens or Tolkien and your child may find this book tedious.