I get my information from websites and books, mostly dictionaries.
If your interested in the Rusyn connection it might be worth your while to visit
www.lemko.org, which has some informative articles. Also the wikipedia articles on Rusyn, Lemko, Boyko, Hutsul. There is also a list of Lemko surnames on the web. Fatula isn't on the list, but Fat, Fatala, and Fatila are. Nothing on the meaning however. Out of curiosity I looked up "fat" in Russian and Ukrainian dictionaries; it means "fop" or "dandy" in both languages.