Opole is covered with a dense bus net. Bus tickets are avilable in newspaper kiosks, usually adjacent to bigger bus stops. A regular ticket costs 2.60 PLN (less than 1 Euro). If there is no kiosk nearby, you may buy a ticket on the bus at the driver (3.00 PLN but the exact amount is required.) To validate your ticket, you simply insert it at one of the readers on the bus. One ticket is valid from the stop you enter the bus to the terminal bus stop.
Taxis from nets are rather cheap. Ask the driver to give you a receipt after payment. The night tariff is more expensive. Call a taxi by mobile phone, e.g. +48 77 19622, +48 603 969622 (be aware that taxi operators and taxi drivers usually are not fluent in English).
In front of the main building, Oleska 48, there are city bicycles for rent.