Quest Giver
While most Quests are given by Saloon NPCs, some are also given by quest givers on the map. Some, like the Ghost town are always there, others appear when certain conditions are met, such as completing another quest. A quest giver does not have to be a person, it can also be a location where something needs to be done. Quest givers are marked on the Minimap with a white dot. They are not shown on the world map. Many quest givers are not unique on the map and can be found in multiple locations so the walking distances aren't too long.
To accept a quest from a quest giver, you need to be at the same location. Some tasks only become visible when you are at the quest giver's location. As of 1.30, many quests from quest givers require the character to be physically located at the quest giver in order to complete that quest. In cases where this is a requirement, a quest will show as FAILED in the Quest Book. If all other quest completion requirements are met, the quest can be completed by returning to the location of the quest giver.
Note that some quest givers will disappear after they are no longer needed, but many are persistent and will always remain on the map. This doesn't necessarily mean they will ever have other quests.
Find quest giver
In some quests you get the task to find quest givers. Not every quest giver can be found in each map section. In most of the quests you get hints about where to find them. If you get the hint to search in the west, then you should just check the western map sections on the world map. The best way to find quest giver is to click through the suggested areas and to check if a new purple dot showed up on the Minimap.
If a quest giver does not show a quest it is mostly caused by not accepting or terminating a quest.
1. The quest giver can be found in the northern areas.
2. The quest giver can be found in the eastern areas.
3. The quest giver can be found in the south west.