I don't have any plans, but I came to the same conclusions you did. I need a small shed, which doesn't show over the fence, for storing the lawnmower, rakes, etc. I like the plastic store-bought sheds well enough, but for that kind of money, I'd just as soon make something custom out of wood.
I was thinking of something more 4'x5'. I would put a door in the 'short' end, just wide enough to push the lawnmower through. Then put brackets for storing tools and stuff in the leftover space (think of it like a 1.5 garage...with a door to pull the car in and a few feet of room on one side to store stuff). I'd make the shed right next to the house (with about 2 feet of room, just enough to get in there to paint and trim out any weeds, etc.) I'd put a decent angle on the roof for rain runoff, and make the low side of the roof just tall enough off the ground for rake storage, etc.
I cannot imagine needing to frame this with full 2x4's...the little 2x3's at HD should be enough. Then just sheath it with a product which matches your house, paint it, roof it, and call it done. I'm just planning on putting patio pavers in for a floor...just enough to keep the mower out of the mud. I suppose your other option would to be to build it with a 'sledge' type floor (a couple of heavy wood joists, with a plywood floor, so you can drag the shed wherever you want, but then you need to build a small ramp for the mower too.
M_P
