There were six of them and I’m not sure which one’s the first book. I looked it up and there are ten or eleven books already. I have to accumulate wealth as soon as possible and motherlode + rosebud + hesoyam. I wish it was that easy.
There are actually some places that offer the first 3 in 1 volume and the next 2 in another, then you could get the others cheaply at goodreads.com.