You can usually collect them pretty well doing slayer assignments, usually 1-2 per assignment. I would use penguin points on dungeoneering first though, until you get to about 50 or so, otherwise you are getting barely any experience from the effigy.
higher level monsters seem to drop them alot more often.
when you get them don't use them on dungeoneering because it'll be a waste of time.
In dungeoneering you need to get the levels in daemonheim because if you don't you don't get tokens.
meaning you can use effigy to get to 80 dung.. but you won't be able to get a chaotic untill you go get 2m xp from daemonheim.