It's the capital city of Osona, a region in the center of the country, 70km north of Barcelona, 80km west of Girona and 130km east of Lleida.
The round about located at this coordinates is quite good to go west (41.92715405695929, 2.2406101251806376). To reach it, take the train station as a reference, there's only one. From there, walk south to the first round about and turn right. Follow straight until you cross another round about and cross it straight to the third and last one. The place is locally known as Can Pamplona due to the hotel and the bar next to the round about. If you get lost, just ask for it and people will tell you the way. Here a small road connecting to the Eix Transversal (C25) starts. Should be easy to catch a ride right there.
The easiest way should be to walk to the roundabout located here (41.96108534240823, 2.2490000749792216). It's almost 4km north of the train station. There is a milk factory called Pascual right next to it with a big parking lot. The roundabouts before could also be good, even to go west towards Girona.
Accommodation and Sleep
It's easy to sleep in any field surrounding the city. Just walk out of it until you feel comfortable enough to pitch your tent or bivouac. Try to avoid entering private propertie though.
Me (Rustypeg) and a friend hitchhiked from the roundabout in Can Pamplona towards Manresa and Montserrat in a sunny morning of May in 2 hours and 6 rides (70km), crossing Manresa on foot.