The reach of some STI levers can be altered, this should help. Also not all drop handlebars are created equal there are many variations on the drop handlebar shape and if your hands really are particularly small then you may need to find a good compromise between the shape of the bar and the reach of the STI levers.
As for which STI's offer reach adjustment, I dont recall, hopefully someone else can advise on that.
Drop bars come in a huge range of shapes and sizes, so the best option is to go and look at/test ride as many bikes as you can. I, and most of the female cyclists are know, are more comfortable with bars with a compact drop, so if your hands are really that small, that might be a good option for you.
If you find a bike that's perfect in every other way except the bars, you can always change them.