Here's a loop drive through the heart of Amish Country in Lancaster County.
Get off the PA Turnpike at exit 247 and take 283 south toward Lancaster. It will be a right exit just after the toll booth. Go as far right in the toll boths as possible.
Take 283 south to US 30 east.
Take route 340 east toward BIrd In Hand and Intercourse. Along this stretch there will be many Amish shops and attractions.
In Intercourse, take 772 east - it is a slight right in the middle of town.
Take 772 east to US 30 east.
You will be on US30 east for a short stretch, then turn right on south route 41 toward Gap.
In Gap take a right turn over the bridge onto route 741 west toward Strasburg. Along this stretch you will be driving through Amish farm country and will see working farms. You will also pass the Strasburg RR. If you have a spare hour, take a ride. You can also take a narrated buggy ride. You will see them along route 340 and there is one at the Red Caboose Motel along route 741. If you are into train layouts and model villages with animation, take in the Choo Choo Barn.
In Strasburg, turn right on north 896. You will pass "The Amish Village" - a compact way to see what Amish life is like.
TUrn left onto US 30 west.
You have 2 options for your continued trip.
Take US 222 north back to the PA Turnpike to the Jersy Turnpike. (3 hours and tolls)
Take US222 north to I78 (3 hours, very slighly shorter and not all interstate type road)
Here are links to the attrations mentioned above:
Tips: There is a Thomas the Tank Engine week at the Strasburg RR from June 16 to 24. You do not want to take the train or stop at the Choo Choo barn that week.
Do not take close up pictures of the Amish. Distant pictures are OK but be discrete. It is against their religous practices to have graven images of themselves.
Stop and eat in the area. Have some shoo fly pie or sticky buns.