Reformation Trust and Ligonier are making the ebook edition of Daniel Hyde’s Welcome to a Reformed Church: A Guide for Pilgrims for free during August.
A large part of the book’s content deals with reformed theological emphases, with about the final third devoted to describing the nature of a local church and its worship.
The blurb:
In this book Daniel Hyde sketches the historical roots of the Reformed churches, their scriptural and confessional basis, their key beliefs, and the ways in which those beliefs are put into practice. The result is a roadmap for those encountering the Reformed world for the first time and a primer for those who want to know more about their Reformed heritage.
This page at Ligonier has links to various formats.
The kindle edition is also currently listed for free at Amazon.