wrt the makeup, following a great suggestion from people on here, I took my DD plus a friend to our local big town where there was a Bobbi Brown outlet. I booked them in for the teenage beauty thing, where they did a wonderful job at demonstrating how to get a natural look. The girls loved it and I was able to take off for a nice relaxing coffee for an hour or so.
The makeover was free, and the people doing it were really, really super with them. The look they achieved was very natural.
As it was for her Birthday, I did spend money on makeup for them once they had finished, but there really was no pressure to buy. I also got her (again on recommendation - I can take no credit here) the Bobbi Brown teenage beauty book, which seems to have some excellent advice and suggestions in.
The results have been fantastic. My DD continues to look beautiful, and (IMHO) significantly better than many of her peers.
It's also provided good, easy present buying opportunities, to get her the decent stuff. Even I can manage that without messing up, again largely with help from the excellent people who work there (no affiliation, btw!)