Yes, you will receive confirmation of any contribution(s)you make on LeatherList.org. PayPal issues e-mailed receipts to contributors, usually within seconds after a contribution has been made.
Please note that each NPO does receive your name and addresses (e-mail and US Mail), and each has its own timeline for sending thanks to contributors, which is the only purpose for their having that data.
Should you have any question about your contribution, PayPal’s customer service can answer it. Leather List itself does not have any access to your account information, as all contributions go directly to the NPOs themselves. (Leather List is supported by a voluntary tip just before you click the Contribute button.)
So please contribute to the NPOs you wish to support!