Most wine regions have a 'wine cooperative' in or near the town, which will offer wine tasting and buying without the need to summon up the courage to knock on the door of a chateau at the end of a long driveway, and without the fear that you will feel pressured into buying anything. These also sell the cheaper local wine 'en vrac' (usually in 5 or 10 litre plastic boxes) - as drunk by the locals, or for home bottling, - and in wine boxes. Ask at the appropriate tourist office.
St Emilion deserves special mention, being listed by UNESCO as a World Heritage Site. The village itself is very, very attractive. The area around St Emilion is less exciting unless you like looking at vineyards, so I think it is best to visit from the 'south of the Dordogne' region as a day out, which is why it is included here. It is found about 45 minutes drive from Bergerac on the road to Bordeaux.
If you are flying into or out of Bordeaux and driving to our region, St Emilion makes the perfect place to break the journey.
Second special mention is to Monbazillac. This time within our region, close to Bergerac, there is a lovely chateau at Monbazillac with views across miles of countryside. The famous wine here is a sweet white dessert wine.
Specific caves that have been recommended include:
Chateau La Colline - At Thenac, between Bergerac and Eymet near Sigoules. and they can deliver wine to you in the UK.
Domaine Amblard - a family owned wine-producer, at St Sernin, next to Duras