Cindy, Navigate to Stitch Works Software --it's the official site of the software. The software is actually called Stitch Works not Crochet Charts. I don't know about this site, Informer.com, but when you download Stitch Works fromm the official website, it's FREE, Open-Source software, so you don't need a serial number. Hope this helps!
You can purchase Crochet Charts by clicking on the "Purchase" link on this page. If you have problems finding it, here's the direct purchase link: http://crochet-charts.software.informer.com/download/?afe767c