The page is located here:
The bare URL brings up a form that allows for a donation in any amount, to any user. To simplify things for your users, we recommend adding two variables to the URL:
These will force the donation to go to your account, saving the user from having to know which email address you use in our system. A URL with them would look like:force_recipient=1
recipient=your@email.address
You can also create links that pre-select the amount to be donated, through these variables:
These must be combined with the force recipient option. A URL taking advantage of them would look something like:force_amt=1
amt=amount
Finally, you can also optionally specify "note" and/or "force_note" variables, to pass through a donation note.