Writing around the period of 130, Papias wrote
([symbol]Ebraidi dialektw ta logia sunetaxato hrmhneusen d auta ws hn dunatos ekastos.[/symbol]) Since the Gospel of Matthew makes the most overt appeals to the Jewish traditions, a tradition grew up that Matthew had originally written his Gospel in Hebrew and that it was later re-written in Greek.
This has led to a lot of acrimonious discussion. Eusebius (ca 291 - ca 341) passed on the comment, but he also indicated a fair amount of personal scorn for the lack of scholarship in the works of Papias. (Indeed, Papias readily admits that he preferred to collect the spoken sayings handed down by people who may have heard someone rather than by relying on mere books.)
Current theories are rather divided between the notion that the Greek Matthew is an original work in Greek, based on its organization and its internal language, (this tends to be the majority opinion), and those who hold that the Greek Matthew is a re-worked version of a Hebrew (or even Aramaic) Matthew, (the minority position). An intermediate position notes that Papias only notes that Mathew recorded the sayings (or words–logia) of Matthew and posits that the Greek Matthew may have been originally written in Greek, but was based, in part, on a Hebrew “sayings of Jesus.”
I can see scripture scholars getting heated defending their pet theories on the subject, but I am not sure why some theologians get caught up in the heat of the discussion.
I have never heard that Mark was written (in whole or in part) in anything other than Greek.
There is some mild speculation that the Letter to the Hebrews might have an earlier Aramaic version, but since it appears to have been written to a more literate Greek-speaking audience (based on style and content), generally it is regarded as having been written in Greek from the beginning.
Aside from the speculations regarding Matthew, I know of no New Testament work that is not presumed to have been written originally in Greek. Greek was both the lingua fraca and the language of the literate in the Eastern Mediterranean (and even, to some extent, in Rome) in the first century and there is not reason (lacking other evidence) to belive that any of the NT was written in any language other than Greek.