You can order birth certificates online from:
certificateservices(a)ons.gov.uk
If you give them the name, date of birth, and place and your credit card
number, they will issue a copy and mail it to you. I've found this very
efficient. If you don't know the reference number (a filing code) it costs
11 pounds or less than $20. If you do know the ref.code it is 8.50 pounds.
It is very important that in the subject line of your email request that you
title it "certificate request QR" This subject line ensures it gets to
the right place. Recent certs. have taken about 3-4 weeks to reach me in
Canada.
Good luck!
Paula Carr
Victoria BC Canada