you could take a beiber bus from nyc to allentown pa (which i assume is the allentown you are talking about) for like 13 bucks, and hitch out of allentown pa or you could take another bieber bus from allentown to philly also for like 13 bucks. if you decide to do this there are pretty frequent csx rides to the north carolina area, not sure if youre into that mode of travel though, NS has a big yard in allentown too, but ive never gone anywhere except east west from there and its kind of sketch its like jammed against a hill, a road, and the canal/creek, never liked it
the allentown bus station is depressing, downtown spanging is weak at best, as it is in most small, depressed, pa cities (allentown, reading, lancaster, york, harrisburg, bethlehem, etc)
do not take a bieber bus to philly if you plan to hitchhike out of philly, you will have to go substantially far outside the city to hitchhike, continue on buses to DC or Richmond instead of trapping yourself in philly
hitching out of allentown for long distance i recommend going to the 78/476/22 interchange west of the city or better yet farther out to fogelsville, hitch west on 78 until you can get to carlisle to catch 81 south and hangout at a truck stop or the rutters. 78 can be intimidating some of the ramps are desolate and in the middle of nowhere in the lehigh valley, 81 in comparison is pretty well traveled and you will be less out of place
avoid 476 north east extension and the generally the turnpike in PA, the rest stops are pretty good and worth spanging if you ever do end up on the turnpike, you shouldn't its east/west, minus that spur by allentown
once you get to 81 its literally a straight shot to 26 which youll catch somewhere near johnson city tenn/ bristol va/tn
are you leaving soon? its cold as fuck...
hope this all makes sense, kind of rambling, let me know if i can elaborate on anything