Because of its gently rolling hills and lack of traffic, Lopez Island is very popular with cyclists; views of the surrounding islands and mountains to the east and west poke out from every turn. Despite being one of the largest San Juan Islands [1], Lopez is probably the friendliest. Waving to passing cars and bicycles is a time-honored local custom, and failure to wave will label you a tourist as surely as a camera around your neck and rubber thongs.
The business center for the island is Lopez Village, where you'll find a scattering of cafés, shops, a museum, stores, and especially real estate offices—which should tell you something about the island’s newfound popularity. A few more businesses can be found along pretty Fisherman Bay—filled with sailboats and other craft—but the rest of the island is essentially undeveloped. Note that many local businesses shut down for the winter.
The Washington State Ferry (206/464-6400, www.wsdot.wa.gov/ferries [2]) docks at the north end of Lopez Island, approximately four miles from Lopez Village. See the Getting to the San Juan Islands [1] information for details on ferry service (including private ferries) and flights to Lopez Island. There is no bus service on Lopez, but A Lopez Cab Courier (360/468-2227) has taxi service and rental cars.
Links:
[1] http://www.moon.com/destinations/washington/san-juan-islands
[2] http://www.wsdot.wa.gov/ferries