Salou is fairly near Barcelona.
Lots of people take a coach trip, or take the train, into Barcelona. Watch your handbag or purse though.
Also, near the Marina, (and in a few other shops in Salou) they offer boat trips and booze cruises.
The local council also run little blue trains round Salou (on the road). It is 2 euros 50 cents per ride, but you can stay on as long as you like.
They are all circulor routes so if you stay on the train you come back to where you started. They run three slightly different routes, numbered L1, L2 and L3.
They are a nice lazy way to see the town and it is nice and cool if it is hot as they have open carriages.
Also there is a tourist information centre near the marina, it is in one of the large houses on the main street behind the marina.