look into blacksmithing.
ABANA and Anvilfire (just google each word for link) are good online sources for blacksmithing.

If you have an oxyacetylene welder you can also use that to spot heat metal to twist it. A rosebud tip will be good to heat up a larger area, but not as good as a forge.
A mig welder will be useless. A tig welder can also be used, but as it heats only a fairly small area without taking a lot of time can only be used for really localized work. But probably would be OK for just bending of thinner rods (e.g. pencil rods) if you really don't have anything else available.

If you want to look into forges, I find propane forges much easier to use than coal forges. And the correct low sulfur coal can be hard to find.