There are tubing "pliers" with rollers sized to fit your tubing. While these are handy for some situations, I recommend finding a bender specifically for the tube you are working. Ridgid and Imperial make good benders. I don't like the 3 in 1 type. For the rear axle, I made a plywood template to match the differential cover diameter. I often use cardboard to draw out complex pieces full size, then lay the tube on it to check as I bend. Learn the difference between left and right measurements or you will be too long or short.
The other thing is a good double lap flaring tool. I have had good luck with Imperial, but prefer the new Ridgid with the thick non slip flare block. If you have much to do it's worth the investment. Good luck.
