Hatha Yoga is basically a general yoga style, most gyms and such that teach it are doing hatha but its not always exactly the same.
I don't think there is any particular yoga for fertility, however there are certain postures that supposedly stimulate reproductive organs by increasing blood flow to that area. You can look some of those up online, however I wouldn't do until you've taken a few classes.
I personally do Iyengar yoga which is a bit more robust style, with a lot of focus on correct psoture, staying in them longer. You may want to start with something less robust though. Try a class through a gym or community center, then maybe move to a yoga studio.
how about Hatha Yoga? anyone heard of it? I am thinking that If I get the DVD there will be days that I will be lazy and not do it? I am thinking of going to a class. anything to keep me from thinking TTC .....LOL
i heared about a dvd called "Yoga 4 Fertility"