Live sand is not necessary. Questionable benefits come from the bagged "live" sand. You can also buy dry aragonite sand (not too coarse) and your LR will seed it pretty quick. Real live sand like what you can get from places like tampabaysaltwater.com is best or you can see if you can obtain a few cups of sand from an established system maybe at your LFS or a fellow reefer. The bagged sand is overpriced IMO. I would shoot for about a 2" bed. Deeper beds can cause problems unless you are doing it remotely (some type of sump). Color is up to you. Most go with white but there is also black aragonite.
Any idea what kind of fish you're going to want?