Probably the most comprehensive resource is Crossing the threshold Toolkit first created by the Diocese of Hereford in 2009, and subsequently updated in 2013. The toolkit offers a step-by-step guide to managing a church building project.
A simplified version of the Crossing the threshold toolkit that is also accompanied by short videos can be found in the Churchcare resources maintained by the Church of England. In particular look at the following pages:
The National Churches Trust has also very useful information about managing building projects.
The Arthur Rank Centre (ARC) is an ecumenical Christian charity with the aim of resourcing rural churches of all denominations. They have a useful resource about opening up churches.