Troyes is a city in the Northeast of France, around 200 Km from Paris
Going East (Germany, etc.)
Place by the number one bus towards Pont-Sainte-Marie and walking from the last stop for 10 minutes to roundabout just North of Troyes (less than 5 KM from the airport). The ticket costs around 2 Euro. There are many roundabouts on this road leading to the A26 Motorway. It took me 5 minutes to get a ride.
Going West (Paris by A5 or D660)
You can easily hitchhike out to the west by walking to the D660, after passing via the bus stop "De Serre". There is a nice roundabout just after, that links to the right road.
There is also this roundabout that is nearer from town, but I haven't tried it yet.
On the D660 there is plenty of places to hitchhike, to continue on this way, or to join the A5 (that I think is tougher since there's not many people taking it from outside Troyes.