There is a networking thread pinned at the top of Behind The Lens ... where photographers, stylists, makeup artists may network for tests (not models, however). It's not for rank beginners, however ... you need to be able to post some of your work so others can see your level of acheivement and decide if they think you would have something to ad to their portfolio. Be sure to read the first post with instructions about what to post in that thread.
I agree about craigs list, model mayhem and other sites like those. If you dig deep enough you might find a few gems, but the majority are just amateurs and mostly very poor ones but, there are a few exceptions. And the models ... oh dear! Most of them are under 5'7" and are not suitable for fashion at all ... only glamour.
So ... octopi is offering a good suggestion ... schools are sometimes a good source. For stylists, consider fashion schools ... maybe work with a few talented students to photopgraph their creations ... they'd love that.
And yes, make sure you work it all out in advance about how and when images will be delivered to them, how many they get, who choses the images they get, whether or not you will retouch them and how the may use them (usually only for self promo ... portfolios, comp cards, etc.). Get all that laid out in writing, in advance ... so there will be no surprises for anyone and that you can deliver what you promise.