There are two sets of Gillespie Family History newsletters in print that I know of. Between the 1970s and 1980s, Robert & Lois Gillespie in Massachusetts produced Gillespie newsletters mainly with USA content, which were donated to a library in Georgia. Most of those issues are in this Canadian Gillespie Library, but are not available for viewing except in person.
I sent out a quarterly, then bi-yearly newsletters for about 14 years between 2001 and 2014 called “Heritage” then “Foot Prints“. Here is an index of some of these later issues over the years, which were sent out free to most Gillespie researchers with a current email on file. Issues in the earliest years were by subscription.
Here is a sample issue of a newsletter for your viewing. It provides an early history of Gillespies in Scotland, which begins on page 11. A link to this study is also provided on the Scotland home page.