Will there be any more of these ?

No more movies, but an upcoming animated series.

That is very hard to say if there will be anymore movies, I know that Neil Patrick Harris tells Harold & Kumar "see you in the fourth one", which may lead you to believe that they are planning another movie. There are movie series that end after the original movie, and 2 sequels meaning 3 movies, and some movie series might have the original film, and then 3 movie sequels leading to 4 films. And sometimes it can be years before another movie can be made, so it is very hard to say if we will see anymore Harold & Kumar movies. And that of course if both John Cho and Kal Penn will want to do another movie. I mean you can't have a Harold & Kumar movie without Harold & Kumar in less you are doing a spinoff.