Where to find a landing page's URL
If you've already created a landing page, go to your Lists tab and click on the list associated with your landing page. Then, click on the Forms tab and on the green Landing pages link to see all the pages associated with the selected list:
Select your landing page to go to its editor, then click on the Open link in the upper right corner:
Your landing page will open in a new browser tab. The URL address of that tab is associated with your landing page, so you can copy it from there.
It's also possible to change the URL of your landing pages. You can change their domain in your account settings. You can also edit individual landing pages directory under the Settings tab within the landing page editor: