City buses and MRT in Taipei are plentiful and frequent, and the fare differs according to the distance traveled. To reach other cities and scenic spots from Taipei, trains and highway bus services are available. More detailed information can be found at the following links. Most drivers do not speak English. So it's a good idea to have hotel personnel write both your destination and your hotel's name and address in Chinese.
Buses are the most important form of public transportation in Taipei.
The tickets are cheap. Foreign currencies can be exchanged at the CKS airport, government-designated and private banks, and hotels. Receipts are given when currency is exchanged, and must be presented in order to exchange unused NT dollars before departure. The currency exchange rate can be obtained by your currency to Taiwan dollars.