I know there are some people who do it around here. But I don't remember their names. So you'll have to rely on luck if you keep expecting it from yahoo (and on patience because you'll be very criticized in the meantime).
Free readings are hard to come by, which is understandable. You can try and search for theme-oriented forums on google. I don't know any but I know they exist. there you might find people who might do it for practice, although many might still be still beginners. Be careful with that.
You can also try collective readings on youtube, some professional tarot readers do it. The downside is that as the name says, it's collective, so there's a lot of energies on the table and some stuff might be right, some stuff might be be wrong.