(Menander Protector, for those of us unused to having his cognomen in English.)

In Greek, certainly, they're easily available on the Internet Archive's archive of out-of-copyright books. There's only one English translation and it's in copyright, so you won't find that online.

Here's a decent article about him on JSTOR. If you don't have JSTOR access, that journal is part of JSTOR's free Register & Read program.

If you want the Greek text, say the word and I'll dig up a link to the Müller edition.