Betty Splendens is always a great place to start.
You will want to read through every single page before you start breeding. Then you will want to join the IBC for only $20. You can find everything you need to know there pertaining to showing.
Don't forget if you are breeding crown tails you will need fairly soft water or all your hard work will be for nothing. Hard water causes their rays (the spikes on their fins) to wrinkle up and/or curl. Double check your water supply before committing to a crown tail.