Contact he railway parcel office at New Delhi Station for the possible to Dhanbad. Only few options will be there as it's passing station and 5 min stoppage. Regarding fare it will cost around rs 2000 approx for railway and 500 for packing and 500 for loading at source station another Rs 100-200 for unloading at DND. Some stations insist to have a ticket by the same train in which now is loaded. Buy a GS ticket or SL WL or confirmed if you are not travelling by that train. See that the train arrives in day time at destination. Fares and prices vary I have given as indication.