Can I recommend a couple of good daytrips (not organized exactly as tours...)?

Go to Aranjuez on the strawberry train (actually, by Sept. that might not run)--Aranjuez is a wonderful town, and the strawberry train is an old steam train (the cars used to be used in coastal areas in the early 30s and 40s and have wooden benches). Once you get there, RENFE has tour guides that take you around the town (includes beautiful botanic gardens, a naval museum, and a castle). When we went in April they served us DELICIOUS strawberries. Yum. :p

Go to Alcalá de Henares on the Cervantes train. Modern train, but the tour guides are dressed inperiod costumes and perform plays both on the train and during the tour of Alcalá (which is the birthplace of Cervantes).

Both these tours run on weekends only. They cost between €20-25 and include snacks on the train as well as the guided tours (and any entrance fees required). Lunches are on you, both towns have a variety of restaurants.

Did you notice that I seem to focus on food... hmmmm. Wonder why?

and a p.s.

Toledo on your own costs €5 roundtrip. It's an easy town to discover on your own. There's a bus from the train station to the town entrance--it's a walkable place. DO spend the whole day there and explore lots of the side streets.