MdMiko,

I'll try to answer some of your questions here. If you are looking to import users in from an external database I would go to http://www.snowcovered.com/ and search for User Import, there are a number of tools available to import users into DNN from outside systems.

As for getting started with learning everything about DNN, there are a few resources available now, and I am tasked with coming up with a training program for DNN, but just started in that role a couple of days ago, so I don't have anything I can offer you from DotNetNuke Corp just yet. But we are definitely working on how to better get people up to speed on DNN, quickly and easily for everyone involved. You might check out http://www.engageuniversity.com in the mean time to get started on a few things.

As for managing news in a DNN website, there are a number of ways to do that, you can use the HTML module like you are doing, or you might check out the Announcements module. There currently aren't any built in modules that will pull in all recent changes like you see on the homepage here at DotNetNuke.com, I believe those are manually controlled right now by our staff.

News categories don't quite exist yet, but check out some of the features that are coming in DotNetNuke 5.3 as noted in this recent blog post, a taxonomy is something featured in that release.

I hope that helps get you started a little bit, feel free to post additional questions here in the forums.

Chris