The local history museum is moderately interesting with a bit of stuff on the history of the region.
Exhibits range from the history of the peoples of the area, wartime artefacts and a exhibition of the wildlife of the area.
Definitely worth at least 30 minutes of your time.
There are two local trains a day to Ussuriysk from Vladivostok, and all the long distance trains headed to Ussuriysk stop here as well, although often at odd times.
Buses from Vladivostok are quite frequent, pretty much every hour.
The train station is actually a fair way from the centre of town, although there are cheap buses that will take you into town for less than 10 roubles.