Before we delve into research in the archives (albeit digital ones), it is worth consulting the large worldwide family tree at MyHeritage, where enthusiastic genealogists share everything they managed to find on their ancestors. Although the data need to be taken with a grain of salt, it may serve as a great stepping stone. Moreover, MyHeritage is linked to other family tree databases (e.g. Geni) and sources (American marriage licenses or lists of passengers coming to New York across the ocean).
Registers of births, marriages and deaths are the main source for research into the historical family. In the Czech Republic, registers have generally been preserved from the period after the Thirty Years´ War onwards. Moreover, we luckily do not need to travel across the country to consult them; thanks to the fast-advancing digitalization we can browse them from the comfort of our home.
Population censuses, address books
For more recent periods we can also make use of population censuses and lists of population. Their availability depends on the individual archives.
Although it may sound somewhat morbid, gravestone inscriptions are an outstanding source of basic information on individuals. Even here, time has moved on and it is not necessary to roam around graveyards in search of dead ancestors.