Your first impression may well be that Venice doesn't have a nightlife. As the last rays of daylight slip away, so, too, do most signs of a bustling town. Boat traffic drops to the occasional vaporetto, shutters roll down, and signs go dark. Even though bacari (wine bars) would seem to be natural after-hours gathering spots, most close before 9 pm.
But boulevardiers, flaneurs, and those who simply enjoy a little after-dinner entertainment can take heart. Sprinkled judiciously around the city's residential-looking calli and campi (streets and squares), you'll stumble upon locali (nightspots) that stay open until 1 or 2 am. Some even offer live music, though rarely past midnight—a city noise ordinance prohibits too much wildness except during Carnevale. Though there are no suitable venues for rock shows, Piazza San Marco has hosted some less-rambunctious concerts on summer evenings. Except for a few lounge bars with dancing, nightlife tends to be student-oriented.
Both private and city museums regularly host major traveling art exhibits, from ancient to contemporary. Classical music buffs can rely on a rich season of concerts, opera, chamber music, and some ballet. Smaller venues and churches offer lower-priced, occasionally free performances that often highlight Venetian and Italian composers. Though the city has no English-language theater, during Carnevale you'll find foreign companies that perform in their mother tongue. All films screened at the Venice Film Festival (some in an ad-hoc amphitheater constructed in Campo San Polo) in late summer are shown in the original language, with subtitles in English, Italian, or both.
There is a variety of resources for finding what's on in Venice. Both the city and the province have tourism offices and associated websites with English versions, turismovenezia.com and comune.venezia.it, respectively. (For the second, click on the "Tourism" tab.) The calendar publication available at the APT tourist offices on the Piazza San Marco and in the Pavilion near the Vallaresso vaporetto stop provides extensive, current information on museums, churches, exhibitions, events day-by-day, useful phone numbers, gondola and taxi fares, opening hours, and more. A Guest in Venice, a monthly bilingual booklet, free at hotels, also includes information about pharmacies, vaporetto and bus lines, and main trains and flights; aguestinvenice.com lists musical, artistic, and sporting events, as does Agenda Venezia (agendavenezia.org). Venezia News, available at newsstands, has similar information but also includes in-depth articles about noteworthy events; listings are bilingual, but most articles are in Italian. Venezia da Vivere is a bilingual guide that comes out seasonally listing nightspots and live music. Try venicexplorer.com for a fantastic map function to find any address in Venice, and venicebanana.com and the 2night.it listings for lots of insider restaurant and entertainment goings-on. Look to musicinvenice.com for a comprehensive calendar of musical events that you can also reserve (they even have a 24-hour phone service). Last but not least, don't ignore the posters you see everywhere in the streets; they're often as current as you can get.