I'm looking for a book (or perhaps an online resource)that has all chord fingerings for all types of chords on all notes.
(major, minor, diminished, augmented, all seventh chord types too.)

Also, a good book or resource on how to be a better improviser too.

While there are *definitely* recommended scale and arpeggio fingerings, to my knowledge chord fingerings aren't really so much of a thing for piano. Maybe someone here knows otherwise.

This is because

* On narrow chords, where the chord fits in the piece as a whole is important. Any given simple triad in some inversion might be fine as 135, or 125, or 124, but if there's, say, a subsequent higher note that needs to be played in a passage it might cause you to advocate for 124 so that 5 is free to play it.

* On wide chords (say, 10ths), your options are limited. You'll do 1 and 5 and then place the other fingers where they fit. Sometimes you'll hit two notes with your thumb if warranted; but the size of the chord generally dictates what your hand needs to do to hit it (or if you need to revoice or roll it).

Where chord fingering is important, often your score will write hints in.

Any other suggestions?

My suggestion: Be patient!

Your post has only been around for a few hours, it is Sunday, and members live in all parts of the world!
I'm sure you'll get more replies later.

practice scales with triads and inversions and your hand will learn common positions which can later be modified as needed. see David Glover's Scale Book.

It depends on the chord. For example, with a simple root position C triad, I can count ten different ways of fingering it, and I can find chords which would demand the use of any one of these ten fingerings.

What style(s) do you have in mind?

For each one (or maybe even everything!), there's no better or more comprehensive guide in my opinion than lessons with an experienced piano teacher that's also an experienced improviser (of whatever style(s)).

As far as introductory texts, these are great starts:

Classical:
http://faculty.oxy.edu/rgrayson/download%20improvisation%20handbook.html
(Richard Grayson published - and updates - this free guide on improvisation in various styles. If you haven't watched or listened to his playing on youtube, I highly recommend it)

Soloing/improvising over standards (a good foot in the door to jazz):
Michael Miller: The Complete Idiot's Guide to Solos and Improvisation

I believe the fingerings you use for chords depends on the size of your hands. For triads, anyway.
For 7th chords, where 4 fingers are used, just use all fingers except for #4 (that being the weakest). For triads, I feel it's what ever works. I just use 1-2-3 in the RH but a child or smaller handed adult won;t be able to do this. I always felt the finger that should not be used is #4, so just work your way around that. There are only 5 fingers to choose from!
Why isn't the html code working here for italics??

I agree that fingerings are different for different hands, but I would not agree to avoid the 4th finger. It is critical in many chords, so get used to it.

Because it uses UBB with square brackets [ ], not HTML with angle brackets < >.

Click on "switch to full reply screen" and click on the italic "I" button to see the code.

It really depends on your hands. You may have a weak 4, but my 4's are stronger than my 5's. I also have some nerve damage affecting my right 2, and to a lesser extent the 1 and 3.

Fingering also depends a lot on the context, what's before and after a particular note or chord. For instance, in the bridge of Katyusha, the left hand goes back and forth between Am and Em. I play them 421 and 542, because for me that's the easy way to do it fast enough.

Fingering is specific like that rather than generic, which is why we write the numbers on the sheet music.