The keys appear at random places. You may find the key in one room, but next time you go into a dungeon, it may be somewhere else. Just look around everywhere. Oh, and you must distinguish keys not only by color, but also by shape - so that would not just be "the yellow key", but "the yellow square key", "the yellow circle key", etc.
If it's to do with Dungeoneering, Find a door with the matching shape and colour.
The keys in dungeoneering appear in random places, so you just have to search for them.
You kill chaos Dwarves there I think, and they drop the key.
sorry you cant make keys on runescape unless of corse it is the crystsal key.
There isn't a key for it unfortunately.
I am sorry, but you can not actually answer this question, because there are many tunnels in RuneScape. Especially for members there are a lot. There are also different keys, for different places and different quests.
A brass key.
In pikachu's snatch
you go through it to find the key to the gym
The white key is actually the yellow key which is located in wavi beach.
Buy it, get it from the Hill giants.
The sentence "Use the blue key, not the yellow key" should use a comma before the phrase "not the yellow key" to separate the two contrasting elements.