I've never seen a pattern for this shape, but I'm envisioning a tube shape for the body with maybe a few decreases opposite each other at the top. Then along one top edge, a rectangular flap, say across 1/3 to 1/2 of the stitches (the same measurement as the inside width of the handle), which you could run under the handle and button or tie on the opposite side. Ok, I haven't allowed for the spout. hmmmm...You could make a half circle bag-shape with a small button-hole type hole for the spout and a larger slot for the handle? The big slot could have a loop and button closure under the handle.
OK, enough envisioning. Here's a pic of the type you're looking for - unfortunately the pattern isn't free: http://www.earthheartdesigns.com/ima...%20teapots.jpg
I can see why you're frustrated -there's nothing out there for you! I see a little math in your future. Sorry.