The Sydney Visitor Centre at The Rocks, First Floor, The Rocks Centre, Corner of Argyle and Playfair streets, The Rocks (tel. 1800/067 676 in Australia, or 02/9240 8788; www.sydneyvisitorcentre.com), is a good place to pick up maps, brochures, Youth Hostel Association (YHA) cards, and general tourist information about Sydney as well as towns in New South Wales. It also sells books, T-shirts, DVDs, postcards, and the like. The office is open daily from 9am to 5pm. There's also the Sydney Visitors Centre Darling Harbour, 33 Wheat Rd., Darling Harbour, near the IMAX Theatre. It's open from 9:30am to 5:30pm daily. You can ask questions by e-mailing them (email@example.com). In Manly, find the Manly Visitors Information Centre (tel. 02/9976 1430) at Manly Wharf (where the ferries come in). It's open Monday to Friday from 9am to 5pm, and on weekends between 10am and 4pm.
Also in The Rocks is the National Parks & Wildlife Centre, in Cadmans Cottage (a little sandstone building, built in 1816, which is set back from the water in front of The Rocks), 110 George St. (tel. 02/9247 5033). This place has lots of national park information and runs boat tours to some of the islands in Sydney Harbour. It's open Monday to Friday 9:30am to 4:30pm, Saturday and Sunday 10am to 4:30pm.
Elsewhere, there are City Host information kiosks, at Martin Place (btw. Elizabeth and Castlereagh sts.), on George Street (adjacent to Sydney Town Hall), and at Circular Quay (corner of Pitt and Alfred sts.). They provide maps, brochures, and advice and are open daily from 9am to 5pm. There's also a Visitor Centre at the international terminal of the airport. If you want to inquire about destinations and holidays in Sydney or the rest of New South Wales, call Tourism New South Wales's help line (tel. 13 20 77 in Australia).
A good website is CitySearch Sydney (www.sydney.citysearch.com.au), for events, entertainment, dining, and shopping. Another is www.sydney.com.