I'll start with the Antonio Villas Boas case. I think I mentioned this one before somewhere but it bears repeating - mainly for its Star Trek style sexual content. It apparently happened in 1957, Antonio Villas Boas was a young Brazilian farmer out working the fields when he encountered a circular spaceship. He was kidnapped by the humanoid occupants of the ship and taken aboard. After being stripped naked and subjected to medical procedures he was then left in a room where he encountered another alien being - this time a female. I'll quote directly from the book now;
...Antonio was shocked to see a beautiful woman enter the room. She was about five foot tall and completely naked. Her face was entirely human, except for her large, catlike eyes and rather pointed chin. She had long white hair, although her pubic hair was bright red ...he and the woman had sex. Her technique was rather unusual: she did not kiss him, but nipped him on the chin and made barking noises.The woman then rubbed her belly and pointed skywards - apparently indicating that she would have his baby up in space somewhere. The book doesn't mention if Captain Kirk was jealous or not.
A more scary tale of red hair visitation apparently occurred at Dakelia Barracks in Cyprus. In 1968 a British Army NCO had an encounter there with a terrifying 'incomplete humanoid being'. It occurred at 3 o'clock in the morning after he was alerted to a strange presence by his Turkish wolfhound growling. After hearing a high-pitched humming sound..
..the soldier moved carefully and silently to the door of his room, while the wolfhound uncharacteristically scampered under the bed and began to whimper.He opened the door and stepped on to the landing, at which point he was confronted by the thing. It's described thusly;
...only the head and shoulders were visible - dressed in a light blue suit with a collarless neck. The scowling face, inclined forward, was bright orange in colour; the hair was red, and the eyes were large and unblinking.He ran back and hid in the room, then picked up an underwater spear and fired it through the door. The humming sound then immediately stopped. He was left shaken by the encounter but made a full recovery, the dog however 'remained fearful of the slightest noise for the rest of its life.'
Rouge hair also cropped up in another case, this time involving a guy named Jose Antonio da Silva. He was out fishing when he was accosted by some space people and dragged aboard their ship.
The beings had waist-long, reddish hair, thick eyebrows, large eyes, ears and wide mouths, and large, crooked noses. They also sported extremely long beards. These strange, dwarf-like creatures took an immediate interest in da Silva's fishing equipment.They eventually returned him - 250 miles from where he had originally been abducted. He later discovered that he'd been gone for four and a half days.
The book also mentioned a broader category of red-haired aliens. These are called Oranges in UFO circles.
The Oranges are said to be quite similar to humans in appearance, although their hair is red, their skin has an orange tone, and there is something of the reptilian in their faces ...it has been suggested that the Oranges are a hybrid race, but one that has been produced through the fusion of humans and Reptoids, rather than humans and Greys.
Looking at all these tales from a red-hair point of view it's interesting that they all fall under the same historic archetypes associated with red hair - sex, fear, dwarfs, dragons.