Are there functioning staking pools in the testnet?

Hi Dima

If you are looking to use CNTools then you should look at the post that @Alexd1985 did names

How to set up a POOL in a few minutes - and register using CNTOOLS

You can go to the Cardano Github pages

Another good resources the Coin Cashew site

Finally another resource is

All of them include input on the testnet also

Kind Regards
Shad