Coming somewhat late to this thread...
Someone mentioned "spirits of salts". In fact, I remember to have written a review on Amazon on this book: to put it short, this is in my view
nota verry good book, as you can probably bring no single process to work properly if you rely on the informations given there. The authors try to cover everything, but really explain very little.
Crawford's "keepersof light" is much better, in fact, I think, a valuable classic, but pretty outmoded in may of its technical details by now.
I recently read Mice Ware's "The Chrysotype Manual", available from
siderotype.com, which does not only cover chrysotypes (gold prints, similar to Platinum prints, but offering other possibilities, like different colours; see also my website), but contains an extensive general introduction into printing with metal salts (i.e. siderotypes) Some parts do not make a very easy read, but I can only recommend the book in the highest terms. It offeres basic insights valuable for different processes. Maybe somewhat taxing for an absolute beginner, but i would still say, why start with something second rate?