As a first step try and find the record on the following web site:

h t t p://manxbmd.com/ [remove the spaces in first 4 letters]

it will help if you know which area of the Island she was born in i.e. Douglas and the East, Peel and the West, Ramsey and the North, or Castletown and the South.

If you want to get a copy of the birth certificate you will need to apply to the Isle of Man General Registry:

www.gov.im/registries/general/civilregistry/

A copy birth certificate cost £7.00 as long as you can give all the relevant info.

DavidR