Welcome to the forum. In the UK there is a company called Haynes that prints workshop manuals, but they don't make a paper version, only an online version. I don't know how good it is. I tend to use this forum as a resource, or YouTube videos. I have a 2015 CRDi and I did replace the starter motor myself, 2 years ago. It wasn't difficult, provided you have some ramps to lift the front wheels so you can work from underneath. Remember to disconnect the battery after the car is in position. My car had done about 144,000 km when the starter motor began to fail. If you look through my previous posts I showed some photos of it. Search for 'servicing starter motor' and you will find the post.