I had ordered live rock twice before online from Drsfosterandsmith.com
The rock was very nice, and the price was good, but since its out of the water for 2 days, I had to re cure it again in a rubber maid container with a
power head and a heater. The stink was so bad for the first week.
They sell live rock via mail order 2 ways, cured and uncured. The cured will have some die off and take about 2 weeks before levels drop, the uncured will take a lot longer.
If you go this route, make sure you get like a 10 or 20 gallon rubbermaid or simalir container and a lid. The lid will keep the stink in pretty good.
My rock took about 2 weeks before the ammonia, and nitrite dropped to zero in the containers. I also did a water change every couple of days.
If you buy live rock online, it will come with directions on how to cure it.
Price it out online vs the store and see. You will prob pay more at the local store, but u wont have to go thru the mess of curing it again.