Hi XXXXXXX~
It's not unusual for a new dog to not eat for a little while when it comes into a new environment. They're still adjusting to the new smells, sounds and activities that go along with the new home.
As long as he's acting normally otherwise (is drinking some, urinating and defecating) and seems playful, then I don't think I'd worry about it just yet. Just leave food available and he'll eat eventually (a healthy dog will never starve himself when food is available..I promise).
Don't try forcing or begging him to eat. Ignore the foodbowl and him when he's near the bowl and he may eat on his own. If you're really worried, you can try tempting him to eat by adding something really yummy (cooked chicken) to the bowl to see if he'll eat that.
Odds are that he's just trying to figure everything out and will eat on his own in a day or so..but if he doesn't eat by Saturday, you might want to have a vet take a peek at him..just to be on the safe side.
I hope this helps!!
Certified Veterinary Technician
Associates Degree in Veterinary Technology. State and Nationally certified.