Central Landscape is about 180 miles from me, but I go there about every two weeks during the season. We run a single axle tractor and big trailer and get almost all of our supplies there, edging, plant material, you name it. They are the most complete landscape supply company in the country, and are nice people besides.
In this area, a lot of steel edging is just plain raw steel from a wholesale metal supply. Most guys buy 1/8" x 4" wide x 20' strips. You put it in, it rusts, but we say "it weathers to a nice natural patina that blends well with the other elements of the landscape." Sounds better than rust.
A lot of people prefer the green painted stuff that comes mainly from home centers, but also a few landscape supply houses handle it. Also 4" wide.
Most all lawns being installed here in new developments are Bermuda. Big time invasive of the landscaping, goes right under the edging. The last couple of years I've been buying steel strips about 8" wide, sinking it about 5 1/2," which pretty well stops the Bermuda, still is exposed just enough to weedeat against.
This spring I am experimenting with painting it green, because some of my customers are having me add landscaping, and the landscaping they already have in their yards is edged with the green painted steel.
I've been getting $2.50 a foot for the 4" installed, am thinking I will need to get about $4 a foot for the painted 8". My cost for the 1/8" x 4" steel is about $13 for 20'. The 8" is lighter gauge, last batch cost me about $2 per 9 1/2' strip because it was scrap from a fabrication job.