Hi,
I keep running into this problem where I have a vocal effect or say, an instrument fade in or fade out, that I apply and then later realize I don’t like, but Audacity gives me no options of removing it! I see an option in the ‘Edit-Undo’ section to take off whatever the very last thing I did was, but there’s no way of going back a few steps and removing the effect specifically - even in the Effects section there’s no way of seeing what effects you currently have, and removing it. I hope I’m explaining this correctly.
Please let me know if you can help 
Thanks!
You can review the project at a previous state using “history” …
http://manual.audacityteam.org/man/Undo,_Redo_and_History
However if you want to remove an effect you applied several effects ago, you have to discard all the subsequent changes,
e.g. undo to the state immediately before you applied the effect you now don’t want.