Just got a block plane from Lowes (the only one on the display). It has a cup on its sole. Is it supposed to be like that?
Most hand planes you buy unless you get a premium hand plane you need to tune. There are several tutorials online on how to do that. http://www.instructables.com/id/Tuning-a-Hand-Plane/
I normally take plane apart and flatten the sole using a granite stone using higher number wet sandpaper, the water will keep the paper sticking to stone.
You can use a permanent marker on sole and when lines disappear your sole is flat.
You should also flatten the back of your blade using same technique.
To get proper bevel I prefer this tool.
I hope this will explain it in more detail.
Now this takes time but the rewards comes when your tool works as it should and you get crisp cuts each time.