This tutorial doesn't tell you how to use Worldcraft, or how to map for Quake in general.
Here's a quick link for that:
First, be sure to grab the map textures that should be found at the downloads section.
When planning the map for NBA, keep the layout simple and quite small. Why? Because the AI is simple, I made a 2 level map, which was horribly large too, the AI got stuck in certain parts of the map. Proper fix for this would be to implement pathfinding, but I've found it to be a bit too slow for the PSP.
You should avoid tight corridors, small doorways, ramps and dead ends too. Just to make it smoother gameplay-wise.
When you're done with the geometry, you're going to need 3 different map entities, besides lights. These are:
-info_player_start, this it the same that Quake uses, place multiple instances of these for multiplayer support.
-misc_shop, you can't find this in the entity list, you create it by creating another entity first and then changing its class to "misc_shop" in the properties. You can place many shops in one map, but not recommended. In Worldcraft the entity is represented as a small purple box, because I don't have .fgd file with the correct size and origin. Place the purple box so that it's halfway inside ground.
-monster_spawn, this is the spawn point for monsters/aliens/bugs, whatever you want to call them. Place many of these all around the map, but avoid corners and dead ends. The code will take care that it never spawns these into the players view.
That's about it.