What kind of embroidery machine to buy?

I started sewing a couple of months ago and I am really getting into it; I love it. I really would like to do embroidery, initials and maybe erflies, cute little things for children's clothing and quilts. I am not sure what to buy though! When I bought my first sewing machine I bought a Singer Tradition. It was just an $80 simple machine so I could see if I would like it. Now I see that you can buy embroidery/sewing combos. Should I buy one of those or just buy a separate embroidery machine? Is there a brand out there better than the other, or certain things I should look for? I really want to try and keep it less than $400. Do you think it is possible to buy a quality embroidery machine for less than that? Thanks!