stut, thanks for the great advice on the LAM Rosso bus! I ended up having 3 hrs to kill at the airport inbound today and decided to go see the tower. The bus was definitely the quickest and easiest way to get there. Here's how it went for those interested:

1) PSA / Pisa Immigration - Arrived from LGW and the line went very fast - UK citizens were waved thru with no questions, I (US citizen) took about 7 sec longer while the officer stamped my passport.

2) Bus Tickets - Upon exiting to landside, the Information booth is on your right. Buy your bus tickets there. See the CPT website in the above post for rates. €0.95 for a 60-min ticket or €1.25 for a 120-min ticket should do it.

3) Left Luggage - The Information booth also handles Left Luggage. The agent will walk you over to security toward the middle of the airport, cut the line, have you put your bag thru the big x-ray machine, then put green security tape around it. The agent will then walk you back to the Information desk and a room on the left side behind the booth where you put your bag. It gets labeled and you get a claim check. You pay €7 (per day) when you pick up your bag - just bring your claim check to the booth.

Incidentally, there was no place to buy a SIM card for GSM mobile phones in the airport. Apparently you have to go to a 'phone center', but the agent at the Information desk didn't know where one was.

4) LAM Rosso Bus - The bus stop is right outside the airport exit by the information desk, a little to the right and across a road. The bus will have the recognizable LAM logo on it and shows "L/R" on the LED display above the door. The buses wait their til their scheduled departure time (see the CPT website). Once the bus departs, you need to validate (timestamp) your ticket yourself using one of the yellow boxes onboard. A recording calls each stop as it is displayed on a monitor in the front of the bus. "Prossima Fermata" = next stop (push one of the red call buttons to request a stop). The Stazione FS (Pisa Centrale train station) stop is about 5 min from the airport and the total ride to Piazza dei Miracoli (where the Tower / Torre is) is 15 min in either direction.

5) Leaning Tower of Pisa - The bus stop is right outside the west gate of the plaza and you can see the tower from there. It's free to walk around the grounds, but you have to purchase a ticket to enter the buildings and I think you need to book in advance if you want to climb the tower. I think the Ticket Office is amongst the souvenir booths on your right as you enter the plaza, about halfway down. For me, 45 min was plenty of time to mosey around, take some photos, and buy some postcards. There are a number of restaurants and cafes in the vicinity, but per bdemaria's advice, I didn't partake.

6) Return to PSA - The bus stop is across the street you arrived on, a little to the left as you exit the west gate. It's about 10 min to Stazione FS (Pisa Centrale) and another 5 min to Aeroporto (PSA) where you started (don't get off by mistake at the 'via Aeroporto' stops, which are on the Airport Road leading to PSA). Don't forget to validate your ticket if you're using a separate return (although no one ever checked, everyone seemed to do so on the honor system).

Very easy round trip if you have an hour or more! I printed a copy of the route map and schedule for the stops in each direction from the CPT website (Aeroporto - Torre and Torre - Aeroporto) and the bus ran pretty much ontime. ^