Hi Jim, I also have a copy of The World Book of 'COULINGs' (not COWLINGs). Our family must be a lot larger than I initially thought, although I knew there were a variety of spellings.
When I bought my copy in 1997, such genealogical gems were frowned upon by serious genealogists. But I saw it as an opportunity because the last chapter was an International Registry of COULINGs taken from a wide variety of databanks. I did not have a computer (or Internet access) then to search these sources myself. So my husband sponsored my next step.... a Mailing Blitz...I wrote a form letter in January 1998 and sent it out to over 500 COULING families around the world!
I'd like to see some of your family genalogy to see if/how it fits together. So, if you have time and would like to send it along, I'd appreciate it.