it's actually fairly simple. Hit P to use Pen Tool - Make sure it is set to Paths not Shape Layer which the icons are found below FILE - EDIT - LAYER - SELECT across the top. Then start clicking all around the object you want cut out until you meet back to beginning which will end your path. Then right click on the image and select make selection The image will now have marching ants. Then hit SHIFT CTRL I to invert the ants and Delete and the background will be deleted.
I hope this helps, I thought I made a tutorial for this but I guess I didn't.