Prevalence of Magic

In the world of Ut'wan Olo'khu, magic is largely uncommon.
As with all things, it does depend on where you are and your luck. While it is uncommon, magic is not unheard of and everyone will have heard of it - even if only in stories. In general, magic users would be viewed on a par with extremely skilled artisans - rare and valued.
When people speak of magic users, they are mostly talking of wizards. But that is mostly because most people who don't interact with magic regularly don't understand the differences between, for example, a wizard and a sorcerer. Most people would be aware of divine magic as being different to arcane magic though.
Your chances of finding magic users increase with population density. Most magic users can be found in large cities. There is the chance to learn from other magic users and to be paid very handsomely for their skills. in fact, the seven elven cities would not exist without the magic of the coral singers. But it is important to note that magic is still not common enough to be 'industrialized'. It is still a specialist skill.
Magic is often used to assist other tasks in being done better or to make life more comfortable for magic users or those who can afford their services. From lights that are brighter than bioluminescence and never dim to prestidigitation assisting in making some otherwise unperformable crafts performable. Even clerics assist with disease control and sanitation assistance when required. 
One city that is particularly noteworthy is the elven city of Tovenar. Tovenar was known for its magic college where magic users flocked to study arcane arts with like minded individuals. Of course, the war changed the focus of the city somewhat and though small, its army with a higher than usual number of war mages was feared.
Most cities would have a number of magic users, large villages and settlements would also tend to have a small number (though they would not necessarily be particularly skilled).
When it comes to small villages and settlements, it would be common to have no magic users. But you also would not be surprised if someone did know a few tricks or had a gift for healing. There are also exceptions - families where magic runs through the family or is taught from generation to generation, the loner mage who wishes for solitude and moves away from the city to a small village or even a cave, covens of druids living in tune with the ocean and with magic. These exceptions would not be common, but occur often enough in stories that they would be considered
Often those who wish to learn or are gifted with magic would be apprenticed to other magic users. Quite often these magic users are quite wealthy - or exceptionally hard working. Some have to mostly figure it out for themselves.
[In more technical terms the game is starting as a low magic world - but not so low magic that it is unheard of. Especially for the PCs. After all, you work for the Archmage of Sieraad. Think of magic a bit like technology in the early Renaissance. There are some advances, but they tend to be concentrated in cities.]