To be honset, I don't think the market would be very big at all. The show entry information provided for most shows gives a lot of detail on how to best photograph your quilt, there are several excellent websites on the subject, lots of quilt shops provide well lit settings for taking the pictures, and even inexpensive digital cameras take good photos for the jury process.
For the Lowell (MA) Quilt Festival, the New England Quilt Museum is providing space and a professional photographer to take entry pictures (free of charge to members, museum entrance fee to non-members).
http://www.lowellquiltfestival.org/q...y-service.html
They also give these reference sources.
http://www.lowellquiltfestival.org/p...our-quilt.html
Your friend might contact the museum for the photographer's name and then contact him/her for pricing info. You're in a comparable, but not competitive, market area so it doesn't seem like it would be any problem. Good luck to her.