I am in the process of figuring out how to get my backyard graded. We also need to put in a storage shed (about 8' x 8') in the back right corner. It needs an even surface to stand on, and with the entire yard graded slightly away from the house, this wont be even.
I'm attaching a crummy paint drawing to show what I mean- this is a side view.
Would it be possible to grade most of it, then level it out so the shed has a stable base to stand on? Might this create any problems down the road? FYI, most of the yard between house and shed is going to be a lawn.
Consider building a timber frame box and filling it with gravel. Just build the box level and your all set. An 8x8 shed means you only have to accomodate grade drop for 8 foot. I'm guessing you may only need one timber up front and maybe two behind. Just sink the bottom timber into the ground a bit to prevent the gravel from leaking out. The water will go around as long as you grade the area in front of the box to go to either side. If done right you can incorporate small raised beds on each side of your shed for flowers and what not. A small ramp will allow access to the shed with a mower etc.
Build a frame and pour a concrete slab works well too. You can grade down and then flat but you will end up with water at the house side of the shed if your not careful or install drains