First, I would order the "Surf Report" for the Dominican Republic. You can find it on Internet at <A HREF="http://www.surfermag.com/travel">www.surfermag.com/travel</A>. It has a very descriptive account of most breaks in the country. The best time to surf the north coast is November to April, but you can also get good waves from passing tropical storms/hurricanes in August - October. For example, TS Debbie is expected to pass north of the Dominican Republic Wednesday, and--if we don't get hit again--produce some big swells.
During the winter, some of the best surf in the Dominican Republic is found between Sosua and Cabarete. About 5 km west of Cabarete is a sand point with consistent swells in the winter called "Hidden Beach." It is near a delayed housing construction area. You can camp for the day, week, or just drive in from your hotel for a few hours. The wind usually picks up onshore in the afternoon, so hit it early to mid-morning, but not too early or you'll get the leftover backwash bounce. It's a golden sand beach with clear water and an offshore reef parallel to the shore about 100 meters out, ridable at 1-3 meters.
You can rent surfboards in Cabarete, which is primarily a windsurfing capital. You'll have to constantly clarify that your interest is in surfing--not windsurfing or sailboarding or wave jumping--when asking about breaks or conditions.
On the north side of Samana, check out Playa Bonita. It is another good winter break just west of Las Terrenas. Playa Grande is also a popular winter spot.
There are good waves year-round on the south coast. It's amazing that the south coast is so consistent with real, open-ocean reef tubes like Rincon, Puerto Rico, i.e, waves that can break boards and cut you up. Before moving to Santo Domingo, I never expected that 90 percent of the time that we go to our favorite break here, there would be ridable waves. Sometimes the swell lasts over a week and I look forward to a flat spell just to rest!
Not much on the east coast near resort areas of Bavaro and Punta Cana, but there are waves a little further north of Bavaro once the barrier reefs break. Also some of the south shore offshore islands have great breaks, but you'll need to charter a boat, and take someone with local knowledge to find the surf.
Some of the most consistent waves are in downtown Santo Domingo (Guibia), but the water is polluted. On a good 4 foot day, you'll find a dozen people right off Maximo Gomez and George Washington Blvd. More, less polluted breaks are east of the capital. The Juan Dolio (an hour east of Santo Domingo) hotel district has many reef breaks that never get crowded. Also try out Barrucho, a half hour south of Barahona. There's a pounding rivermouth there that breaks year-round. A new resort hotel within walking distance of the break just opened a few months ago.
Dominican surfers are very good. Some are world-class and would win international competitions overseas should they compete. They are friendly and willing to share their waves with visitors as long as you respect their country and people, and practice good environmental habits. Try to learn a little Spanish before your arrive. It will make your visit more fun.
