Hello, I recently published my first eBook. It's an art book collection of hand drawn postcards and decorated envelopes I have sent out through the mail. It's 83 pages, lavishly illustrated, including a couple of videos. It's called "Postcards & Doodles" (by Tim Hodge) and is $3.99 in the US. I am looking for inexpensive ways to advertise and promote this book. It's sort of for a niche audience, so any help or suggestions would be appreciated.