I started shooting Maternity and Newborn pics this week.. and I have come to the realization that I prefer Zoom lenses.. Zooming in to the hand, the arms, ears of a newborn... and zooming out to get the background.. etc.. I actually ended up using the 18-55IS kit lens.. but I am missing the wider apperture of my nifty fifty even! (and even my useless-piece-of-cr@p-needs-calibration-sigma30mm)
I will be upgrading to a T2i by the end of the month and would like to buy a zoom lens.. I don't want to spend more than $800 on it..
I tried the 18-135mm at a local photography show.. I like it but anything in the price range with a wider apperture than f3.5?
Thanks guys!!

So, I just find a spot with a window in the client's house and shoot there.. 

), you should be able to crop in on things like the hands and face and still have perfectly acceptable images. 
