A good starting point is Martin Brasier's book Microfossils'. But then again, when you get down to it, naming macrofossils is not so easy if you want to be really accurate. Two groups of organisms are common, the foraminifera and the ostracoda. The tests can be made of sediment grains or secreted calcium carbonate, and come in a wide variety of shapes. The test can have one or several chambers.
Simple forms have one chamber in the shape of a tube, vase or spiral.
Multi-chambered forms can have the chambers in a straight or curved line, can be spiralled or helical or even more complex. Ostracods are bivalved crustaceans and could be crudely described as being small shrimps in a mussel shell'. They live in freshwater and marine environments and are free-swimming or bottom dwelling. The type of microfossils you find can tell you a lot about the depositional environment. Foraminifera only live in marine or brackish water environments.