Hi,
I usually just lurk in teenagers, but I very nearly have one 
dd1 is 13 in a few weeks and we are desperately looking for a new dress for her party, it really could do with being on line shopping as both dd have sporting activities that keeps us very busy over Friday nights and weekends, and I work full time but she is at that inbetweeny stage!
She doesn't really like the kids stuff at next, very, matalan etc and easily gets into a size six in adult stuff but so we ordered a dress from Misguided and one from asos, but it's too long as it is designed for an adult, where do you get your teen girls party gear from (she about 5 foot)
There seems to be a real gap in the market for girls her age or am I looking in the wrong palces?