I would agree with the courses listed so far. Yale and Hotchkiss are two of my favorites. If you are there for the architecture you will love them, but if you are there for optimal conditions you will likely be disappointed. East Mountain, one of the Waterbury munis designed by Wayne Stiles, also falls into this category.
Shorehaven Golf Club in Norwalk is another one of my favorites. Designed by Willie Park and built by Robert White.
Country Club of Waterbury is a very good Ross course. The more I play it the more I love it.
Torrington Country Club is a very good Orrin Smith design which is still very much intact. Torrington is a club that clearly appreciates their history.
Bulls Bridge in South Kent, CT is a fun modern course, if you like Mountain golf.
Shuttle Meadow, which Mark mentioned is my favorite course in Hartford County. It’s a very authentic Willie Park design. Much of the original design still remains from 1916.
Tamarack in Greenwich is another fun course with optimal conditioning.
I always enjoy New Haven CC; Woodway CC and Wee Burn in Darien. Rockrimmon on the border of CT is another solid course with nine by Robert Trent Jones Sr. and nine by Orrin Smith.
Birchwood (9-holer) and Westport Longshore (public) in Westport are both fun courses too. Both are good examples of Orrin Smith’s work. Birchwood is often recognized as one of the best nine-hole courses in the country.
Litchfield County is full of old-school nine hole courses. Hotchkiss, Green Woods, Lake Waramaug, Norfolk Country Club (which I haven’t played, but heard great things). The atmosphere at these clubs is quintessential New England.
Many courses in CT are a smorgasbord of architects work. You might find three or four different styles throughout the 9 or 18 holes. It’s a negative for people who like one theme throughout the course, but it can be a positive if you are looking to experience the different eras of architecture all in one place. CC of Fairfield would likely fall into this category. Beautiful setting along the shore, optimal conditioning, but it’s a mish-mash of Raynor, Tillinghast, Robert Trent Jones Sr. and Cornish. Wee Burn is a great example of Emmets work, but it has been slightly downgraded by adding Fazio bunkers that don’t gel with Emmets greens. I don’t mind Fazio’s bunkers at Bulls Bridge because they fit in with his design, but at Wee Burn they don’t look right to my eye. I just hope they suit the members eye, because they are the ones paying for it.