Just figure out what play they're from, and when the play was written. That should let you know whether or not it's contemporary.
"You can only become truly accomplished at something you love. Don't make money your goal. Instead, pursue the things you love doing, and do them so well that people can't take their eyes off you."
- Maya Angelou
"Online" is the worst place to find monologues-- get thee to a bookstore or a library, find yourself a collection of contemporary monologues (one that I often suggest is called "Moving Parts: Monologues from Contemporary Plays"). That's the best place to start...
"Inside every actor there is a Tiger, a Pig, an Ass, and a Nightingale. You never know which one is going to show up."
-John Michael Higgins in FOR YOUR CONSIDERATION
Well, yes, if you need a monologue ASAP a monologue book is the way to go. However, for the long term, try to read/see as many plays as possible as part of your "theater education," and you will come to find monologues that work for you. Sometimes I'll see a play and buy the script just so I can use a particular monologue as an audition piece.
But yeah, don't go online for monologues. I've tried--there's nothing of worth on there (unless of course, you're buying a script).