I just purchased some leader wire ( barracuda style) for spinner making. It is hard to get the coil memory out of it,which is definitely a detriment to a spinner ( will wobble if they arent straight. I am bendin the wire the old fashioned way ( needle nose pliers). I have seen wire tools for 50.00 and that's a little to much for me. I do suggest to check out Jed Davis's book on steelhead/ salmon spinner fishing. It shows alot of good tricks about spinners (i.e. size, color, building). I think after I use the wire already purchased, I will purchase the pre bent wire from mortac. They use the slide on and bend at the top method, to where there is no rough edge protruding at the bottom.
Pliers work, you just have to be patient and get the bends in the right places. Good Luck!