This could maybe help you.
Surname database [/li]
If you find your last name here, you are most probably of Serb ancestry (regardless of which religion). Of course obvious surnames like Hrvat, Horvat, Hrvatin are not of Serb origin, it is also stated that they are immigrants from Trieste, northern Croatia/Slovenia region (now Italy). The surnames stated that they originate from the Serb clans or old Serbia in general, are old Serb. This being one of the Serb ethnic territories, means that all migrations be it to Krajina, Slavonia, Bosnia, Vojvodina, Sumadija etc. that occurred later on, after the fall of the Serbian Empire and the Ottoman genocide upon these parts, started from there. All medieval Serb dynasties originated from there as well.
As for the naming among Serbs.
It was built by your given name, the name of your father (отачаство) and the name of the last known progenitor of your kin (sometimes brotherhood, or clan). So if your name was Radoslav, your fathers Vukan, and the progenitors Petar. Your full name would be Radoslav Vukanov(sometimes with -ić) Petrović, meaning Radoslav the son of Vukan, from the brotherhood of the Petrovići, the descendants of Petar.
One has to understand that up until the 19th century, we did not bear surnames in the modern meaning, but were recognised by our fathers names, and/or by our brotherhood or clan affiliation. Only after the documenting of the population started, were the surnames written down.
Some examples bearing the fathers name are: Marko Miljanov Popović, Vuk Stefanović Karadžić