Hi Will,
You asked a mouthfull.
You need several things to get started with armour.
You need a dishing or sinking stump. This can be as simple as a depression shaped like a bowl carved in a stump or as nice as the bottom of a large oxygen bottle.
You will need a sinking hammer and a planishing hammer. A sinking hammer is a hammer with a domed surface that has been mirror polished, you can reshape a single jack or use the ball end of a ball pien but this leaves lumpier results. For a planishing hammer you can use a mirror polished hammer face, an autobody hammer works but is light, a standard claw hammer, etc.
You will need a way to cut your steel. Hammer and chisel (slow but sure), Jigsaw with metal cutting blade (nosy), a hand held power shear, or my favorite a bench mounted throatless shear ( a decent one may be found at harbor freight).
You will need a planishing stake this make be a mirror polished dumbell from walmart, A 2 and a half inch trailer hitch welded to a stake and the flat spot ground smooth and round, a large mill ball welded to a stake, a shot put welded to a stake, or you can also use a large four inch fence ball post from your local fencing supply. A planishing stake should be kept mirror polished this helps you later on in your work.
I would reccomend a workbench of some type ( a decent heavy wood bench dedicated to a stake plate and to hold your other work tools woudl be nice).
I would reccomend a bench vise.
As for an anvil, you really don't need one for armour. You just need a heavy metal surface to set rivets on. You could do this on the small anvil face of your bench vise, or get a convienant hunk of steel, a piece of rail road track, a small length of i-beam, use your imagination and find it cheap from the scrap yard.
You will need a way to polish your armour (if this is your goal) or you can leave it rough from the hammer. Polishing involves the use of a buffer and a way to sand your armour. It may be as simple as an expanding drum sander on your buffing motor (an inexpensive one may be obtained at Harbor freight, I use one from Grizzly), to a high end belt grinder. Buffing starts with a sisal buff ( a sisal rope buff would be really nice and aggressive) and black rouge, followed by cotton buffs with a white or green compound.
You will need a way to make holes, a drill and bits works well, but I prefer a punch (faster and more accurate). If you use a drill be sure to use a center punch to keep your bit from wandering.
A good book on how to make 14th century armour is sold by Brian Price and is often abreviated as TOMAR. Also here is a ok .pdf on how to get started in armour.
http://www.brighthelm.org/armour/
You will also need patterns. See
http://www.thearmourarchive.org for patterns and nice information and also
http://www.arador.com for other articles on making armour.
Clothing is a whole other can of worms. There are several good patterns out there, but a lot of them you will have to create from scratch. Use proper cloth such as cotton, Linen and wool.
If you are thinking of making mail, that is another topic.
The main trick is to get in, make some mistakes and learn from them (much like learning to fight with a sword), then practice, practice, practice.
When you really start to under stand the steel you may wish to get a forge and start raising instead of sinking your armour. This is how they made helmets from one sheet of steel instead of the modern method of welding them from 2 to 3 pieces.
hope this helps, and good luck.
Brian Hunt
GFS
P.S. look at as many pictures as you can of the orginal armour from musuems, private collections, etc. This will help your eye start to learn the proper lines for armour.
