I presume you've looked into what it says about incense in The Tale of Genji? This page from UVa is tantalizing... and the mention of Genji-mon and awase-kô is also relevant I suppose. And try The Floating Bridge of Dreams for another bit.
ooooh! and amazon.com has this: The Book of Incense : Enjoying the Traditional Art of Japanese Scents by Kiyoko Morita List Price: $9.95 Our Price: $8.95...