So, I assume that there is no real way to find a list of the tags that I have used for the books I've tagged.  I would like the opportunity to go back and redo (or undo!) any tags that I entered that may have had mistakes in them or are no longer necessary, etc. 

I can't do that, right?

I believe you have to do it by book and there is no master list.

now if you have the books on your TBR shelf or bookshelf or books you've read or reminder list, they are all right there and you can go down each book and make your changes.

This isn't much help, but I've had the same problem. The only thing I could come up with -

If you know that you tagged some books "want it", tag another random book the same way.  Refresh the page so you can see the tag and then click the tag to see the list of books tagged that way and remove the tag from any you want to remove it from.  Sort of the annoying, hard way - but not really, since there's no easy way!

Good news is that Searchable Tags is coming, at least that's what the site admins have said.  The bad news is that it isn't here yet, so to "fix" your tags you have to click on the tag you want to fix by finding a book you've tagged with that tag, which will bring up a list of books tagged with that tag.  You can then go in and fix your book tags from the list that's brought up.

Anna is right, if you can't find a book that you've tagged with the tag you want to fix, just create another tag on a book same as the one you want to fix, then refresh the page so you can see the tags on the book including the one you just added, then click on it to bring up all the books tagged with that tag.  Then you can edit your tags from that list.

I figured this would be a problem so I started deleting them as the books got to me.  I only tag books on my WL as a result.  Wouldn't want them to bug everybody forever!

Ruth