Here are some more specific tips:Ī Path of Iron - Triggered by trying to grab Melus Petelius' Claymore by his wife's grave in Brindle Home.
The one in Anvil would point to Shadows in a Struggle for Power and the one in Bruma to The Skyrim Bandit Clans, for example. And generally, reading the notifications you'll find in cities would start you out on them. A Path of Iron is the only questline with a clearcut start - the other ones can be triggered on different locations/occasions. Lots of people have asked for details on how to start the quests in OOO 1.32. Unless specifically noted this comes from the old guide.
Many of these questions come straight from Devnull's guide and they deserve all the credit. If you have questions, ask them and I will put them here too. Mostly the Frequently Asked Questions are questions I had when playing OOO.