1. Jane Austen's clear prose provides a perfect sample of third person. Though Pride and Prejudice is very much Elizabeth Bennet's story, the narrator is not Elizabeth Bennet. "I" or "we" would only occur within quotations:
When Jane and Elizabeth were alone, the former, who had been cautious in her praise of Mr. Bingley before, expressed to her sister how very much she admired him.2. We can find a more recent example of third person in Joseph Heller's Catch-22. Again, though it's Yossarian's story, he isn't telling the story to us. Note the dialogue tags (e.g., "he answered" and "Orr said.") In third person, you'll never see "I said" or "we said."
"He is just what a young man ought to be," said she, "sensible, good humoured, lively; and I never saw such happy manners! -- so much ease, with such perfect good breeding!"
"He is also handsome," replied Elizabeth, "which a young man ought likewise to be, if he possibly can. His character is thereby complete."
"What are you doing?" Yossarian asked guardedly when he entered the tent, although he saw at once.3. Finally, contrast these with a first person example from Moby-Dick. In this case, the story is told by Ishmael, and he speaks directly to the reader. Everything is from his perspective: we can only see what he sees and what he tells us. In this case, the dialogue tags, of course, vary between "I said," when Ishmael is talking, and "he answered," when the other person speaks.
"There's a leak here," Orr said. "I'm trying to fix it."
"Please stop it," said Yossarian. "You're making me nervous."
"When I was a kid," Orr replied, "I used to walk around all day with crab apples in my cheeks. One in each cheek."
Yossarian put aside his musette bag from which he had begun removing his toilet articles and braced himself suspiciously. A minute passed. "Why?" he found himself forced to ask finally.
Orr tittered triumphantly. "Because they're better than horse chestnuts," he answered.
"Landlord!" said I, "what sort of chap is he -- does he always keep such late hours?" It was now hard upon twelve o'clock.
The landlord chuckled again with his lean chuckle, and seemed to be mightily tickled at something beyond my comprehension. "No," he answered, "generally he's an early bird -- airley to bed and airley to rise -- yea, he's the bird what catches the worm. -- But to-night he went out a peddling, you see, and I don't see what on airth keeps him so late, unless, may be, he can't sell his head."
"Can't sell his head? -- What sort of a bamboozingly story is this you are telling me?" getting into a towering rage. "Do you pretend to say, landlord, that this harpooneer is actually engaged this blessed Saturday night, or rather Sunday morning, in peddling his head around this town?"