If your character needs the recipe for a writ, go to the nearest brewer. They should have writs of the level, and the one below, each character's crafting level. that should make it easy. But make sure it's that character buying it.
The other thing to note is that the writs are different between Alliances. If you get the writ in AD (I think that's where Spiceberry Chai is needed) then you need to go to a brewer in AD. The EP and DC ones will have the recipes for their own Alliance's writs. It doesn't matter what Alliance your character belongs to, just where you get the writ.