Aside from cut/pasting the table cells over and over again until you’ve got 250 rows, I don’t really know an easier way… maybe an HTML generator has such a feature?
You can still use monster pics, but if you’re going to, make sure that you separate the Pokemon pages into separate numbering groups… for example, make a page for Pokemon numbers 1-50, then one for 51-100, and so on in that fashion. And make an option for an enemy page without pictures as well.