Hi Suzanne. The accepted time for planting holly is late autumn to early spring, so you should be OK now. Just a couple of points to ponder:-

Plant it where it is going to stay. They don't like being moved around. And if you want berries then, unless it is a self fertile variety, you will need two bushes, one male and one female. And you can't go by the name, the Golden King is for example, a berry bearing one so is female and the Golden Queen is the male. They were named in the days of chauvinistic male horticulturalists. So if in doubt and it is not labeled, ask whoever bought it for you for full details.