We build quite a few bumpers at my place for rigs of various persuasions, with and without winches, etc.
What we do to figure out the bumper we want is to lay it all out using either stiff cardboard (similar thickness to the steel we'll be using to fabricate it) or thin plywood/paneling. We mock up a bumper, including mounts out of the wood or cardboard, taping it all together, then transfer each piece to steel. Cut it out with what you have -- we use a combination of tools, from a sawzall to a skil saw with metal cutting blade, to cut off wheels, chop saw, and once in a while (if I have a used on in stock) plasma cutter, which is the absolute best.
Lay out everything, then tack-weld it all together. Check fitment and straightness (make sure your welds do not warp everything!) and then go to burning... Grind to suit your needs, and finally paint as desired.
It's mostly time-consuming, but not all that difficult to build some very nice looking bumpers using this technique. We use a few different "cheats" to get some desired features, like using rounded box steel to get a rounded edge on parts instead of a square edge, pipe or tube to get smooth corners, etc.
I'm also working on a couple simple dies for my 20 ton press to press out some shapes that we use often. They are not rocket science -- just a couple pieces of pipe used to form a round piece or a couple pieces of angle iron to form square edges. I'm also working on a "dimple" die to press those cool looking dimpled holes in stuff -- they both strengthen a sheet, and look great.
