You can pick up bus and train timetables for most routes at local tourist offices. The main train stations are in Oxford and Banbury and have frequent connections to London Paddington and Euston, Hereford, Birmingham, Bristol and Scotland.
The main bus operators are the Oxford Bus Company (01865-785400; www.oxfordbus.co.uk) and Stagecoach (01865-772250; www.stagecoachbus.com/oxfordshire). If you plan to do a lot of travelling by bus, Stagecoach offers 1-/7-/14-day bus passes for unlimited use of its services in southern Britain (excluding London) for £6/18/34.
Alternatively, Cotswold Roaming (01865-308300; www.cotswold-roaming.co.uk) runs guided bus tours from Oxford between April and October. Half-day tours run to Blenheim Palace (adult/under 15 years £16/10) and the Cotswolds (adult/under 15 years £19/11), while full-day tours (£30/18) go to Bath and Castle Combe, and the Cotswolds.