It would probably be easiest to keep your archived music and shoutcast databases separate, as they are really different kinds of media and tailoring a database/import for both might be difficult (i.e. remove your shoutcast path from F2>Basic). For illustrative purposes, download a skin that has a net radio/shoutcast page and database already built into it, assuming you haven't already (Baddabing's Redeux II, for example, which can be found
here. Be sure to read the .pdf linked in his first post on how to set up the skin properly).
Once you have all the Redeux files in their proper place, hit F2, go into Skins, select Redeux from the drop down list and then hit restart. Once Redeux is loaded, hit F2 again and go to Databases > Shoutcast-Radio>Edit and see how the database is organized (in this case, by genre, and then each entry has a title, URL, etc.).
From here, you can either continue using this skin and edit the database with your new entries, delete the included entries and replace yours, or use Redeux as a template for creating your own shoutcast database. To do that, you will need to go under the import tab, type a name into the "New DB" field, and hit add. Once created, you can edit the database to your liking (either by filling in the fields by hand, or your could try a custom import, using the music template perhaps and .pls as your lone extension).
To create a screen for your shoutcasts from scratch, hit Pause/Break from within a skin to bring up the Skin Editor. Hit the "Screen" tab and then create a new screen or clone another (it will clone whatever screen you are viewing, with the new name you enter into that field). Use the "Goto" tab to go to that screen (it may go there by default), back to Screen tab, choose "Add" and fill the Category field with the name of your choice (radio stations or some such). That will create a highlighted box. To fill the box with your database, go to Item > Category, make sure the Display field has "%display%" in it and under the Database tab below, choose your database. From there you can tailor how it looks with the Layout tab.
That should get your started. I'm a complete moron compared to most of the folks around here, but even I got the hang of customizing Xlobby after not too long...
[If I made any mistakes or gave bad advice, please feel free to correct me].