I have a lot of articles that I've written that I want to assemble into one or more ebooks.

I can easily format each as a PDF file, but I don't know what software to use to merge them all, in the correct order, and at the same time create a table of contents that updates every time I add a new file.

Can anyone help me?

I have created a tutorial website with about 150 articles, so a page at a time just won't work

Of course I searched and searched for those terms but to no avail, which is why I have asked all of you for help.