I got the best price from this website. It was very easy to buy. I printed my tickets and took them along which saved me a lot of waiting time in the queue.I bought the touristic bus tour for Barcelona I strongly reccomend them. You get to see the major sites there are 3 routes this bus takes you on the red,green,blue route the route goes anti clock wise so plan were you would like to stop accordingly. I would recommend the 2 day ticket if you are not planning to buy a travel card as the bus covers most of Barcelona you can stop of and jump back on when ever you like. We thourally enjoyed our day.