Well my first attempt at hens turned out to all be roosters...yep every one. My advice on this would either get them from some place that can sex them positively (if this is important to you) or get them a little bit older (couple months) and see if you can tell the difference. Also, you might want to consider the breed (just do a search on this) if you are interested in a certain type or characteristic. Otherwise this site has loads of great content to help answer just about any question you may have.
I love my hens...great joy to be around...the roosters I HAD...not so much...