What are neodymium magnets made from and how are they made?

Neodymium magnets are actually composed of neodymium, iron and boron (they are also referred to as NIB or NdFeB magnets).  The powdered mixture is pressed under great pressure into molds.  The material is then sintered (heated under a vacuum), cooled, and then ground or sliced into the desired shape.  Coatings are then applied if required.  Finally, the blank magnets are magnetized by exposing them to a very powerful magnetic field in excess of 30 KOe.

How is the strength of a magnet measured?

Gaussmeters are used to measure the magnetic field density at the surface of the magnet. This is referred to as the surface field and is measured in Gauss (or Tesla).  Pull Force Testers are used to test the holding force of a magnet that is in contact with a flat steel plate. Pull forces are measured in pounds (or kilograms).

Will a magnet with a 20 lb pull force lift a 20 lb object?

Because pull force values are tested under laboratory conditions, you probably won't achieve the same holding force under real world conditions. The effective pull force is reduced by uneven contact with the metal surface, pulling in a direction that is not perpendicular to the steel, attaching to metal that is thinner than ideal, surface coatings, and other factors.