My strategy for when I want or need something -- I say in Global Chat that I want or need it, and then a Mail Frog appears! If you want some currants, say something about it in Global, and a Magic Mail Frog may come your way! I am ready to return this favor. I have and I will! Pay it forward and such...
However, when I need currants, I mine a bunch and then sell it to a tool vendor.