Our pack has been using Scout Track for several years. They are at
www.scouttrack.com and for $40 per year, they do a great job of allowing you to track pack and den membership, contact info, advancement for ALL aspects of scouts and offer other services, such as bulletin boards and calendars. We have been really pleased with them, and I can't see doing advancement without it. The really great thing is that it is web-based, so all the den leaders (or even parents/scouts if you choose to allow it) can enter things themselves, rather than sending everything to the advancement coordinator to enter. The best $40 we ever spent. I dont know of any downsides to it.