Japan Rail Pass / Exchange Order??

Question, I visisited the japanrailpass.net website and read the sticky concerning JR travel in Japan but I am still a litlle fuzzy on a few things:

It is my understanding that you have to obtain the Exchange Order before you leave to Japan, and then take it with your passport to an exchange office once you arrive in Japan and trade it for the JR Pass. My question is, do you have to buy an Exchange Order AND the JR Pass seperately? Or do you have to buy the Exchange Order and then just trade it for the JR Pass?

You turn in the Exchange Order to receive a JAPAN RAIL PASS at a JR station that has a JAPAN RAIL PASS exchange office. You can also obtain an exchange order for a regional pass (JR Hokkaido / JR East / JR West / JR Kyushu) after arriving in Japan.