I haven't seen much in the way of Door County reviews on CH, so I thought I'd contribute my own findings from our recent visit over Fourth of July weekend.
JJ's Waterfront -- Mrs Brewer and I had a lovely sunset dinner at JJ's in Sister Bay. Mrs B started with truffled pappardelle in a Parmesan fondue, followed by the veal osso bucco; I started with charred tomato lobster bisque, followed by dayboat scallops with cilantro corn and sweet potato-bacon ravioli (sounds odd, but it worked). Everything was very good, but the truffled pappardelle stole the show. Overall, good food, friendly and attentive service, and a very pretty view of the sunset over Sister Bay harbor. A bit on the pricey side for the quality, but not outrageous, given location and the likely cost of bringing in high-quality ingredients to Sister Bay.
Wave Pointe -- Wave Pointe is a smallish resort/marina on Little Sturgeon Bay (S of Sturgeon Bay on the Bay side). This was my first experience there, as we were drawn by rumors of a $6 early-bird (pre-5pm) lake perch dinner at their bar. It turned out to be true, and we each enjoyed 4 above-average butterfly fillets, fries, coleslaw, and bread for practically pocket change. An incredible value, especially for a transplanted Sconnie who can no longer find a good Friday perch fry at home. A very solid and respectable representation of your traditional WI bar perch fry.
Malvitz Bay Farm fruit "stand" -- Just west of Stevenson Pier Rd on County C is the Malvitz family farm, which includes a drive-up (air conditioned!) fruit stand, selling strawberries, raspberries, sweet and tart cherries, peas, and jams made from their produce. The raspberries, rainier cherries, and jam were all very good, and worth a stop if you're in the area and interested in local produce.
Any other little Door County treasures off the beaten track that people have found? Other favorites for us that weren't included in this visit are Marchant's grocery in Brussels (great bakery and butcher shop) and Sweetie Pies, south of Fish Creek (ROCKIN' pies!).