If the car's been sitting on a lot for a while and only driven slowly and occasionally, that can happen....even to new cars. The first thing I'd try is a fresh oil change (using a good brand oil, preferably a good synthetic oil) and give it what's termed an "italian tune up", a highly spirited test drive for about 20 minutes or so at higher than normal RPMS (lower gears) while making sure you don't overheat (unlikely but I'm throwing that in).

If after doing that you still get lifter noise, then have it looked at by someone who knows that engine (most likely only a dealer tech?).