Romulan society is highly hierarchazid and so is their naming system. Basically, Rihannsu can be belong to a noble house or be a commoner.
Rihannsu who belong to noble houses will have three names:
On the Romulan Third (last) name, there must be a prefix as follows:
Example: House "Valdran"
A commoner will have only a FIRST name and a SECOND name.
Romulans have a matriarchal society, so after the marriage, the male is the one adopted into his wife's house. So, his his mother's house will be used with the prefix "e-" (as a middle name) and his wife house will be used with the " tr' " prefix as the last surname.
Ex: So, after Kaol i-Dhael tr'Erik marries Isha t'Val, his name changes to Kaol i-Dhael e-Erik tr'Val.
Two good places to start are "Memory Alpha" and "Memory Beta". They have very large databanks.
Another way is to search on Romulan Dictonaries available online and look for words that can relate to your character. For example, a "beloved child" can be called A'Rhea.
Romulan are quite formal, so be careful when addressing a superior officer. Better be safe than sorry! *Evil Grin*.
They also seldom share their given names with anyone. And when they do, it means they respect you a lot. It is quite disrespectful to call someone for their first name unless you are alone and the person had shared it with you.
Basically, you should address the Galae personnel by:
Unlike Starfleet, the Romulan ranks arevnever shortened. An erei'Arrain, is not called Arrain, they are called erei'Arrain. A khre'Riov is not called Riov, but khre'Riov.