As AD advised, the house builder bible, or get home building and renovating magazine, this has a £psm guide for various parts of the country, and loads of useful info.
I have built over 10 in my time, and now usually have some build or renovation project on the go at all times, although I now just sell them on, or rent out, however, there are still things that catch you out, so do as much research as possible before, such as ground conditions, and pipes or cables on the land, and specialist finishes, such as slate or stone that planners may insist on.
It’s a great, rewarding thing to build your own home, so long as it’s done right, and rolling your sleeves up and getting stuck in, even more rewarding in the end. Good luck