You would say "¿Dónde está mi gato, señor?"
Reverendo Señor
gracias señor
Gracias, senor (tilde, ~, on the 'n')
¿Que paso, senor?
Sí, señor. ¿A qué hora?
"Ese es un burro bonito, senor" that's how you say it
Señor, le doy la más cordial bienvenida.
Entiendo, señor
La señora O'Leary, it's pronounced, according to the IPA for Spanish: [la. se.'ɲo.ɾa o̯. le̯a.'ɾi]
You say, "Buen señor, ¿Dónde está mí dinero?" Spanish requires that you put someone up on a pedestal before you snatch it out from under them. That's why the Buen señor goes first.
Senor in Spanish means sir.
Names, especially sir-names, are not translated unless the owner of that name uses a translation.