Good advice, but I'd take it further. Don't start on Pt/Pd. Get yourself 
sorted out on something that is dirt cheap such as cyanotype before you 
think about touching the noble (and expensive) metals.
I've got negatives that can be printed pretty well on both cyanotype and 
platinum by the way - you can control the contrast of both processes to 
some extent.
It might even (though heresy to say so here) be worth trying platinum on 
machine coated paper before you go on to coat your own - if the Palladio 
materials are stil available. 
Peter Marshall
On Fixing Shadows and elsewhere:
http://www.people.virginia.edu/~ds8s
Family Pictures, German Indications, London demonstrations & 
The Buildings of London etc: http://www.spelthorne.ac.uk/pm/