Focusing on Objects in Blender?

How can I focus on an object. Like pushing "F" in Unity? By the way I'm using Blender 2.57.

 

Numpad ".". Or you can go to a local view, with Numpad "/", so you´ll only see that object centered in your view, and nothing more.

 

You can click in the viewport where you want to go with the left mouse button and hit "c" to center it at the spot where the red cursor circle is at. Be careful with this, because if you're in perspective mode and you've been rotating the scene around in different directions, the cursor is not going to be placed where it looks like and you'll zoom out in space somewhere. The best way to use this to move around with is just occasionally, change to orthographic view, then choose Top and click where you want to be, hit C, then change to Front and do it again, then the Side. This will make sure the cursor is exactly centered in the viewport. That will let you rotate around for a while and pick new spots until it starts getting sideways again.

The Numpad method is a good one for moving around the model as well. Certain creation modes like rotating duplicates and that kind of thing depend on which view you are looking at and where the cursor is at. So you have to remember that if you're using it to build something like that you're not going to want to use it to move around with.

EDIT: I just noticed that you are using 2.57, so I don't know whether or not this technique still works, as I understand it's very different than 2.49, which I am using.

 

You can also use Shift + B then draw a box and Blender will zoom to that area.