Making concentric circles in GIMP

I have a single layer image that is 480px square, which I am created with GIMP (it is blank). How can I make: 1. Three concentric circles (the center being at 240,240 px) with radii 240, 180, and 60. 2. Impose a 120px square .png image into the smallest circle, with the center of the circle matching 60,60 px in the image, and cut of the parts of the image that don't fit in the circle. 3. Type in some text and have it wrap around in a circle between the outermost and middle circles. Honestly, this is the only time I plan to use this software, and it is very confusing to me.