There is a solid family of artists here in HMS forums.... we cover a wide range of industry topics.
Most of the Casting Calls and Bookings on MM that I've participated in were for Portfolio Work.
The opportunities available really depend on the KIND of Clients you want to build your business around. Bridal? Print work? Movies......
Take a look at the Castings in YOUR area to see what kind of opportunities there are for you.
It would also be time well spent to read up on the FAQ and Search topics such as "Kit Fee" and "when to start charging" and "portfolio". There's been a TON of advise offered by tenured professionals over the years.
Welcome. When I first signed on I got a lot of paying work through the site. However there is way more TFP work offered then anything else. If your trying to build a book its a great way to get started. However if your looking to pay bills, not so much. Good luck, have fun and keep posting. Everyone has something to share. R-