I had this evening the opportunity to visit my local roleplaying game store. Difficult choices as usual. The sourcebooks are very tempting but their price always makes me wince. Finally I went home with one book for worldbuilding and one about magic. I have read them until now. The worldbuilding book is somewhat disappointing. Too many listings with medieval wares and goods. But a few tidbits are nonetheless interesting. The other one is better. It provides me with some direction to develop my own magic classes and system.