This is what was THE standard for pastured hogs in the midwest for the last 50 years until CAFO's took over:
http://www.port-a-hut.com/livestock-shelters.cfm
They may be expensive for you--shipping can be more than the
shelters. But they
should give an idea.
One of the large
local goat ranches uses fiberglass
underground fuel tanks that failed inspection--never had fuel in them and were either not made right or damaged in transport. Quarters them into four huts. Strong enough to be buried like a wofati, they were the only thing his bucks couldn't destroy.
We used a standard carport available from a big box store. Added sides to make a barn/garage and use a tarp flap door in front for the winter to hold some heat in.
Heat lamps always worry me in barns, good deep bedding should be more than enough. Those pigs will burrow down into a pile of
straw and be cozy.
Hog panels are incredibly useful things to have around the farm. They aren't really that easy to move as rotational grazing, but having them to pen the hogs OUT of new plantings is really useful.
You need really solid perimeter
fence. Then any temporary
fence can work. I prefer rope/braid over tape--tape takes more space and is a pain to get in the clips. But animals can see it much easier so it is a better visual barrier for animals that care.
http://www.kencove.com/
http://www.premier1supplies.com/
Those are two of the bigger
online fence suppliers. Pick a mains charger if you have access to power--they run a LOT hotter and just less to worry about. They are NOT rainproof, though so they need shelter (at least a
bucket over the top if on a post). Otherwise get a 12v charger and a deep cycle battery and a small
solar panel separately. The
solar chargers just are not hot enough IMO or have enough battery or panel for winter or long rainy spells.
Also buy the name brand posts, the O'Briens may cost 50% more but last 3 times longer. If you are running out long fence and moving it a lot, you will want the geared reels--they really speed up moving the fence.
Walter Jeffreys can tell you a lot more on how to rotate hogs.