I was coerced into quilting just over a year ago by a wonderful friend of mine - she took me to a fabric shop (that counts as coercion, doesn't it) - and I got a Singer Confidence Quilter at Joanne's. It does everything I, as a beginning quilter, want it to do. I can sew straight stitches, fun stitches, and I can FMQ on it. I didn't want to spend an arm and a leg on it because I wasn't sure I would stick with it. Turns out, I'm hooked! We just bought a house, so when things sort of stabilize for us I plan in upgrading to a more high-end machine.
Does your friend sew already? If she's just trying it out, I'd definitely steer her toward Walmart of Joanne's. Just have her make sure the machine will do what she wants it to do. For instance, on one of the low-end Berninas (a Bernette?) you couldn't drop the feed dogs, which, depending in your FMQ style, makes FMQ difficult.
Whatever she chooses, wish her happy sewing!