Based on the level of respect or formality, you can say "Where's the tourist office?" in Korean in 3 ways:

• Informal: gwangwang samuso-ga eodi-ya? (관광사무소가 어디야?), gwangwang samuso-ga eodi-i? (관광사무소가 어디니?)
• Formal: gwangwang samuso-ga eodi-yeyo? (관광사무소가 어디예요?), gwangwang samuso-ga eodi-ipnigga? (관광사무소가 어디입니까?)
• Very Formal: gwangwang samuso-ga eodi-ipnigga? (관광사무소가 어디입니까?)

- where: eodi (어디), eodi-e (어디에), eodi-eseo (어디에서)
- is: itda (있다)
- tourist: yeohaengja (여행자)
- office: samusil (사무실), samuso (사무소)
- tourist office: gwangwang samuso (관광 사무소)

Please refer to How to pronounce Korean Alphabet for the English pronunciation in this answer.