What is with all the talk of a Ph.D. being a "post graduate degree", I'm guessing everyone who says that has never been to graduate school.
Ask any graduate student or graduate school and you will be told that a Ph.D. is a graduate degree. A law degree or medical degree could be termed a graduate degree but the more technical term is that they are professional degrees (they generally get a lot less respect in the academic world than a research based Ph.D.).
If you want to differentiate between a Ph.D. and a masters degree you could talk about "terminal degrees" which refers to the highest degree in a field. However, at times that is a doctorate and at times it is a masters. In law, the basic professional degree (the JD) is termed a doctorate, and the higher level degree, the terminal degree in the field, is a masters (L.L.M.).
If you want to use the terms correctly, post-graduate study would be a post-doctoral fellowship (a low paid research position usually) for a Ph.D., a fellowship or clerking for a lawyer, or the internships and residency (and sometimes a research fellowship) for a medical doctor.
Anyway, with that done, my education: Bachelors in psychology, an additional 24 credits in education for my teaching certification, currently studying for a masters in reading and literacy, after my masters I'll take a post-masters certificate in reading or administration (maybe an additional masters degree at Johns Hopkins), and I may go on for a Ph.D. or Ed.D. (Doctor of Education) in special education or educational psychology.