I’ll assume (you know what they say about that word) by your not knowing what Ectoplasm is, that you haven’t done the Anvil side quest “Where Sprits have Lease” (buying a house in Anvil) or “The Ghost Ship of Anvil” (Talk to everyone around the docks especially on the Ships harbored there). Either quest will gives you the ectoplasm you need to complete the Fighter’s Guild Quest.
Originally Posted by Cygnus Q'ol
Is there a secret area in which they are abundant?
Do what stoffe and ChaiNz.2da wrote and you will find more than enough Ninroot, just remember to keep your eyes and more importantly your ears open. Running along any shore line killing mud crabs and you will find plenty very soon and increase your skills at the same time. I actually do this in sneak mode and my little female wood elf is at master level sneak at level 7.
Have you been to Dive Rock yet? The view is incredible on a clear day with the Xbox 360 and a HDTV.
Hope you have more will power than me and can put the controller down long enough to get some sleep. Last night was the first time I’ve been home and not played Oblivion at all since I got the game