There is no download link because the application is discontinued. I've searched through the web and found the official website linked on the Archive.ORG website which means that it has been discontinued (domain included). This is the reason why you won't find a download link anymore, but worry not as there are plenty alternatives to NotepadXP.
For example, there is an app called Notepad++ which is superior to any notepad applications ever released since it supports plugins, development languages, formatting, etc.
