These are the New Testament references to Luke in the NRSV translation:
“Epaphras, my fellow prisoner, in Christ Jesus, sends greetings to you, and so do Mark, Aristarchus, Demas, and Luke, my fellow workers.” (Philemon 1:23-24)
“Luke, the beloved physician, and Demas greet you.” (Colossians 4:14) [note that Luke is not included among the circumcised co-workers of Paul in Colossians 4:10-11]
“Only Luke is with me. Get Mark and bring him with you, for he is useful in my ministry.” (2 Timothy 4:11) [note that Paul is described as completed deserted by his co-workers while he was imprisoned in Rome with the exception of Timothy]
We also have a much fuller biography, or more probably hagiography, about Saint Luke in the so-called Anti-Marcionite and Monarchian prologues. Check out Ben C. Smith’s reproduction of the Latin prologues (though the Anti-Marcionite prologue to Luke has a Greek original) at his website Text Excavation. What is interesting is that the prologues describe Luke as a Syrian, more specifically an Antiochene, who lived a celibate life for 84 or 74 years before he died in either Thebes or Bithynia.