JRT puppy crying/barking non-stop

Our little puppy will be completing 12 weeks nxt wk and we got him when he was only 8 wks old. Unfortunately me and my husband work full time and we have been living him in the shed (with flap entrance), in his cage since (we put the pen just outside the flap - which i have just removed now). At first, i was going back once a day to check on him or a friend and all the updates we had was that the dog was fine, not crying. Last few days i had the neighbours going mad at our door step saying that the dog has been crying/barking non stop ALL DAY. I have ordered your book together with a anti-barking colar (which hasnt arrived yet) to see what else i can do to avoid disturbing the neighbours. They know he is a puppy and only time to get him settled but is there any tips you could give to us???? The garden is full of toys and i even put the radio outside for him. I am hoping that once he has his last injection - nxt wk - and get into a proper walking routine he will settles down......please help us!!!