1. the updater is the easiest way to find and update your ace mods. i am surprised you haven't heard of it. it's been out for a long while now. you can find it here: http://www.wowace.com/wiki/WowAceUpdater
2. as for the off site link i would personally not use a un-official site to update any ace mods that is where most of account security issues pop up from.
This would be even better if it was remotely accurate. I have it intsalled with no problems and its showing erbs where there are none and same with mining. Where you show 10 plants i see 0 and where you dont show them maybe 1 pops up every once in a while. I just downloaded the files with the recent date. I'm in silvermoon and it seems way off.
The data comes from www.wowhead.com. And Wowhead's data, in turn, comes from players running its data gathering addon and now and then uploading it to the site. So, if you're finding lots of nodes where the current data shows none, install it, go to those nodes, and upload the resulting savedvariables. At some point, once other players confirm your findings, these nodes will appear in Cartographer_Data.