Your request is very general and you will probably have better luck getting answers to more precise questions when you are a little bit further along the way.
Still, a good way to get started would be to look at examples in the Models Library (available from the File menu inside NetLogo). The Ants model, for example, does involve agents looking for a target object and coming back to their base.
As for communicating the direction and distance of the target, the distance
and towards
primitives should be exactly what you need. These primitives take the world's topology into account, so you should not have to place your base in the center for "easier calculations."