Ganoderma, Artists Fungs/conk is excellent. As well as Cramp balls & Birch Polypore.
Personally had no trouble using it dried with no other prep but a different technique than using prepared Amadou. Simply use a saw or knife to saw/scrape a pile of dust from the trama layer, spread it out & gently pat it a little flat retaining the air gaps. Drop sparks onto the heap - can take a few goes depending weather you use Iron pyrites, flint & steel or ferrocium rods - strangely I find the first & last easiest - dropping sparks downward off a trad flint & steel ain't so easy because it involves a striking motion whereas the other two can be done with a more controlled grinding action.
The dried ganoderma does not catch sparks from a trad flint & steel when used in the convetional way nearly as well as the prepared stuff. Boiling for a few hours in hardwood ash solution & beating out works very well i my experience - no real need for bought stuff.
Here is a copy of a post I put up elsewhere about Artists Fungus Amadou...
Just a little bit about making Amadou tinder from Artists fungus (Ganoderma applanatum)...
First track & stalk some fungus. Commonly found on dead Beech trees.
Locate the Trama layer & remove the hard upper dermis & the spore tubes.
Boil the Trama in hard wood ash solution for 8hours or more if you can be bothered - the alkali will de-nature the carbon in the fungus IIRC.
Finally bash the b'jesus out of it & let it dry.
Use as you would charcloth - it takes sparks from flint & steel very nicely when roughed up a bit.
Happy burnin'...
Ta.
