You can search for the parish you are interested in either by using map based navigation (if you know where the parish is but not it's name) or by using text based navigation (if you know part or all of the parish name).
Map based Search
Click on the appropriate District.
Use the first listbox to select a specific District or the whole county.
Use the second listbox to scroll to the required Parish, or highlight the listbox and type a letter repeatedly to scroll through parishes starting with that letter.
If you are unable to locate the required parish using the above method, you can also search the site for all pages containing the parish name.