The main source for Sophocles the Man is the ancient "Life of Sophocles" - existing as sort of preface to his plays. Here are some gems - although the Life quotes some sources, without any other means of checking up on them some of this material should possibly be taken with a grain of salt:
His father Sophilos was believed by some to have been a carpenter or smith or a sword - maker. Most probably, though, he owned an "armaments business" which employed carpenters and smiths. The Life thinks it improbable that Sophocles could have become a general and friend of Pericles if his father had been a mere workman (so much for Athenian democracy!) - also he'd have been pilloried in comedy (as Euripides was for supposedly having a greengrocer as a mother) - and Sophocles is always mentioned by Aristophanes with greatest respect.
He was an Athenian, from the deme (village community) of Colonus - where his last play is set. Check the ode to the place in Oedipus at Colonus line 668ff. His family was well off (as you'd expect if the father was an industrialist). As a boy he won prizes for wrestling and music - and as a 16 year old, was chosen to lead the boys' chorus (singing and dancing) which celebrated the Athenian victory over the Persians at the Battle of Salamis (480 BC). [Supposedly Euripides was born on the same day, while Aeschylus had of course fought in the battle - this is a neat way to remember the age gap between the three great tragedians.] The Life says the boys were naked and shiny with oil - presumably young Sophocles would not have been chosen for this unless he was exceptionally good-looking!
To start with he acted in his plays as well as writing them - his Nausicaa in the Laundresses (based on Odyssey 6 - not surviving , alas!) was particularly remembered (significantly a girl's part? There were no actresses in ancient drama). But he gave up acting because of his weak voice (Greek microphonia) - he remained a good lyre-player, and his "official" portrait in the Painted Stoa showed him playing one. He founded a club (thiasos) for students of the arts.
His character was such that "everyone liked him". He served Athens as a general (this was an elected post in Athens - each of the ten "tribes" - constituencies - chose one each year). Sophocles was elected twice (in 440 and again later - supposedly due to the success of Antigone) - and was also chosen as Hellenotamias (Treasurer of the Imperial Fund), and was appointed special commissioner (proboulos) to clear up the mess after the failure of the Athenian adventure in Sicily. The Life calls him philathenaiotatos - very patriotic indeed! He refused invitations from numerous kings to go and live elsewhere. He had two sons by two marriages - both became tragedians. One, Iophon, brought a lawsuit against him (in his 90s) saying he was gaga and should hand over his estate to his son. He read out Oedipus at Colonus as his defence!
He was severely religious - and let his house be used for worship of the healing god Asclepius while a temple was being built. When a gold crown was stolen from the Acropolis, Heracles appeared to him in a dream and told him where it was!
He was born around 496 and died in 406 BC and thus lived to be over 90 - Oedipus at Colonus must rank as one of the most amazing achievements of old age in all art. There are various accounts of his death - did he choke on an unripe grape, or was he reading the Antigone (aloud - silent reading was unknown to the ancients) when his voice froze in mid-sentence and he gave up the ghost?
He wrote 123 plays and won 24 victories (ie 96 of his plays won first prize, as they were always produced in fours). He never came third (ie last) in a dramatic competition. Seven plays survive - in order probably Ajax (?), Antigone, Oedipus the King, Trachiniae, Electra, Philoctetes (409 BC) and Oedipus at Colonus (produced after his death, in 401). Note that he never wrote "trilogies", and the three Theban plays are separated by decades. His first play was put on in 468 - nearly 20 years before the first drama which survives - so there is no such thing as a youthful or immature work of Sophocles!
Because of the attractiveness of his verse - the "honey" - he was called "the bee". His character was summed up by the comic writer Aristophanes as "he always took life as it came."
Sources: Life of Sophocles (anon); Inscriptions; Plutarch, Life of Pericles; Aristophanes, Frogs