Fighting them would be a bit different from other mobs, in that attacking with Unarmed Combat would result in additional damage from it's quills. Using a weapon is highly recommended.
From what I quickly google searched, they don't seem to live in northern europe. So they would more likely appear in the warmer areas of the Hearthlands.
(This guy here lost a leg from a trap)

The last time they were brought up was in 2010. viewtopic.php?f=5&t=5250&p=60022&hilit=porcupine#p60022