Having a custom sized channel formed rather than going with tubing can be a huge cost effective way to go as well. Any good fab shop with a big enough press and shear can make whatever size you want keeping you from being limited to nominal sizes of tubing. Also, going that route, you can mix and match your material thicknesses and save on weight. Say you don't necessarily need to go 1/4" for everything... maybe just in the middle for a winch mount. Yet another benefit to the cost is that a lot of shops have smaller pieces of material kicking around that they love to get rid of so it doesn't clog up their racks... smaller pieces will save you big time from having to buy an entire sheet of steel when you don’t need it.
Here's mine:
For both the front and rear, they cost me $40 in material (granted, I worked at a fab shop at the time). The front weights in at around 120 with the winch (Warn 8024s are stupid heavy) and the rear weights about 75 without the tire on it. As far as time is concerned, I really didn't pay much attention as I just worked on it when I had time over my lunch breaks.