Ok, I would be willing to beat your buying cured live rock! If thats the case all you need to do is put it into your tank. No rinsing is needed. If it is uncured you will need to cure it by putting it into a tank of its own and run it for a few weeks, or make up a gl of salt water, put the new rock in it, and brush off all the dead stuff! After this you could put it into your display, but if you have a high bio load I WOULD NOT DO THIS. You will still run the risk of killing your fish if it is low, but it can be done. I did this with my tank, but all I had was a few dansals. They pulled through.
Good luck
Little