Shape drawing tool?

[blaireau]

I'd love to be able to make panels for my comic, but I can't find a simple tool that will help draw them. I know I can make a rectangle or a circle with the selection tool and then kind of trace a line around the inside, but that's sloppy and inconvenient. I can also trace a circle or square stencil, but then there's no way to adjust the size or stretch the shape.
I was wondering if there was a tool that could actually draw rectangles, squares, or circles the same way that Sketchbook or MS Paint does (click and drag.)