Santa Ana is a large city but is easily navigated, as most everything you need is immediately on or near Parque Libertad (the center of the city). The main east-west thoroughfare near the central plaza is Calle Libertad Poniente, which becomes Libertad Oriente east of Parque Libertad. And the main north-south route is Avenida Independencia Sur, which becomes Independencia Norte north of the plaza. The character of the surrounding neighborhoods around Parque Libertad can change quickly, especially after dark, so don't wander too far off the main plaza.
Santa Ana does not have a tourist office, so your best source of tourist information will be your hotel staff or an English-language tour guide provided by a company such as Nahua Tours (tel. 503/7874-8402; www.nahuatours.com). If you speak Spanish, Santa Ana's Casa de la Cultura (2a Calle Poniente; tel. 503/2447-0084) can also provide information.
The Guatemalan border is only 1 hour away, and Santa Ana is the last major town on the way. The border crossing is at San Cristóbal and is open 24 hours. Bus no. 236 leaves every 20 minutes from Santa Ana from 5:30am to 9pm and costs 50¢. The Especial buses are much more comfortable and go all the way to Guatemala City, taking 4 hours and costing $12.