Link to places and church records: http://www.westpreussen.de/cms/ct/standesamtsregister/quellen.php?ID=195
Online church records on Polish site: https://www.genealogiawarchiwach.pl
Link to CD's available for Koszalin including Prechlau. See "My Pomerania" http://mypomerania.com/kirchenbucher-and-standesamter-on-cd-koszalin/
http://www.westpreussen.de/cms/ct/kirchenbuecher/quellen.php?ID=644
Index to church records: http://www.ptg.gda.pl/index.php/certificate/action/searchB/
Zachodniopoorskie Towarzy: www.ztgpomerania.pl
Poznan Project has some records from Kreis Flatow: http://poznan-project.psnc.pl/search.php
Church records in East and West Prussia indexed: http://namensindex.vffow.de/kirchen.php
Archiwum.Koszalin-Kolobrzeg: http://www.archiwum.koszalin.opoka.org.pl/ksiegi_rz.html [Archives has Catholic and Evangelical records]. A list of available parishes is available on the site.
https://www.szukajwarchiwach.gov.pl/de/o-serwisie
Church books duplicates : https://zbc.ksiaznica.szczecin.pl//dlibra/metadatasearch?action=AdvancedSearchAction&type=-3&val1=Type:ksi%C4%99ga+metrykalna