For a relatively small town, Sancti Spíritus is rather spread out. However, you're unlikely to spend much time beyond the old town, where you can easily walk everywhere. You'll only need a taxi (or horse-drawn coche) for getting to the bus terminal, train station, or your hotel, if you choose to stay at one of the inconveniently located, large hotels on the outskirts of town.
The closest Sancti Spíritus comes to having a tourist information office is the travel agency Cubatur (tel. 41/32-8518), Máximo Gómez 7 on the west side of Plaza Sánchez. Cubatur also offers hotel discounts and discounted set meals at various restaurants in the city, including Quinta Santa Elena and Restaurant Mesón de la Plaza; ask for details.
The Banco Financiero Internacional, Independencia 2 between Plaza Sánchez and Honorato (tel. 41/32-8479), is open Monday through Friday from 8:30am to 3:30pm. The CADECA branch at Independencia 31 (tel. 41/32-8535) is open Monday through Saturday from 8am to 4:30pm and Sunday from 8am to 11:30am.
If you need medical attention, Hospital Provincial Camilo Cienfuegos is located on Carretera Central at Bartolomé Masó (tel. 41/32-4017).
You can make long-distance or international phone calls or log on for CUC$6 per hour with the Etecsa card at the Etecsa office on Independencia 10 Sur between Plaza Sánchez and Honorato opposite the CADECA; it's open daily from 8:30am to 7:30pm. The main post office is now in the same building.