We went to St Dogmaels Abbey on a beautiful, sunny day in June and it was great! We had previously visited Cilgerran Castle nearby so had bought a guidebook (which covered both sites as well as St David's Cathedral) which was excellent as it provided us with a tour around the abbey as well as an insight into the day-to-day life of the monks living there. However, there were also information boards dotted around the site which were useful.
The information centre contained some more history and background as well as a café which was doing a roaring trade.
You can get here by bus or it's a pleasant, easy walk from nearby Cardigan, which is also worth a visit if you are in the area.