What are the rulings on visiting museums and tourist sites, and the rulings on those who work in them? Are there any studies or references on this topic?

To answer your question, you can refer to previous answers on the website that address the concept of tourism, its types, and its rulings, as well as the ruling on traveling for tourism to disbelieving and immoral countries, and traveling to Islamic countries where immorality is widespread. There are also specialized books such as "Ahkam Al-Siyaha wa Atharuha" (Rulings of Tourism and its Effects) by Hashim Naqour, and "Ahkam Al-Siyaha wa Nasa'ih wa Tawjihat lil-Sa'ihin wal-Sa'ihat" (Rulings of Tourism and Advice and Guidance for Tourists) by Sheikh Ibn Jibreen, in addition to a fatwa by Sheikh Ibn Baz on "Hukm Ta'dhim Al-Athar" (The Ruling on Glorifying Antiquities). Furthermore, there are two unpublished master's theses: "Ahkam Al-Sa'ih Ghair Al-Muslim fi Al-Jazira Al-Arabiya" (Rulings for the Non-Muslim Tourist in the Arabian Peninsula) by Abdul Mohsen Al-Ghaith, and "Al-Siyaha fi Al-Islam" (Tourism in Islam) by Abdullah Al-Khudair.