Talsi is a town in Latvia
Talsi is small town, so you can walk from one side to another in less then 30 minutes. There is very good public bus system all around Talsi distric and among other regions. There is even bus circulating around the town during the day.
The only problem can be if you are coming from Riga and the driver leaves you on the A10 just before the exit to Talsi (most drivers are doing so as they are heading to Ventspils). The best idea is to walk by the road in direction of Talsi (on the right) and start hitchhiking again just after you leave on the exit (about ~300 m away).