New for 2012 is a ticket that gives unlimited travel on local buses and trains.
Unlimited rail travel is allowed on the Oxford to Moreton in the Marsh line and the Swindon - Stroud - Gloucester - Ashchurch lines.
On local buses any bus within the Cotswolds Area of Outstanding Natural Beauty that Bourton falls in to.
2012 prices are - 1 day - Adult £10, with a railcard £8.30 and child £5.00. For 3 consecutive days - adult £ £25, with a railcard £20 and child £12.50.
Very good value.
There is a truly massive car park just outside Bourton's village centre (which in itself should tell you how popular it is in season).
Follow the signs. It's much better than faffing around trying to find somewhere to park in the village itself (most spaces there are time-limited anyway).
Costs roughly 1GBP per hour, although cost goes down the longer you pay for. About 5 minutes walk into the village centre.
There has not been a train service to the village for many years - shortsighted cuts by people with no forethought left a beautiful village that is so popular without a train service. There are local buses and the main route is the Cheltenham to Moreton in the Marsh service although there are others.
The link has details.