Yes to the first question, mostly yes to the second. Scholars have found thousands of inscriptions written in Etruscan. The most common by far are inscriptions in tombs and funerary stele, but there are also tablets, votive gifts, coins, and other small objects with Etruscan writing- this was clearly a literate society. The Romans even ended up adopting the alphabet used by the Etruscans for written Latin (although some letters were changed).

The problem is, no one knows what they say, beyond a few hundred words, mostly that were adopted into Latin or Greek. Etruscan is not an Indo-European language, and shows only limited similarities to any other language- and the languages that it might be closest to (Rhaetian and Lemnian) are just as extinct and have even fewer written examples. Latin words that are believed to have Etruscan roots include: persona (like a theater persona, it is likely this is where the word 'person' came from), nepos (nephew), and fenestra (window).

Based on archaeological evidence, we know quite a bit about Etruscan funerary customs and the Etruscan religion (and these of course are the most prevalent extant sources of the Etruscan language). But what we don't have is history, written by the Etruscans (and if we somehow we do, we can't read it)- so for that we are forced to learn about their history through Roman perspectives. For the Romans, the Etruscans were dangerous rivals, and the origin for Tarquinius Superbus- the last tyrannical king of Rome whose history is treated as a moral lesson in later centuries about the dangers of monarchy . And the most complete record we have, of course, is Livy, writing several centuries after the assimilation of the Etruscans into the Roman Republic.