The nominations for the 2016 Hugo Awards have just opened: http://www.thehugoawards.org/2016/01/2016-hugo-campbell-award-1941-retro-hugo-award-nominations-now-open/
Letters to Tiptree (http://www.twelfthplanetpress.com/products/ebooks/letters-to-tiptree where you can also read some of the essays for free) is eligible for Best Related Work this year.
The book is available on Amazon (http://www.amazon.com/Letters-Tiptree-Alexandra-Pierce-ebook/dp/B014WF9Z86) and other e-book retailers.
An excerpt is available at Tor.com: http://www.tor.com/2015/08/12/excerpts-letters-to-tiptree-brit-mandelo/
Many reviews (average rating right now 4.36) have been posted at Goodreads.com: http://www.goodreads.com/book/show/26120369-letters-to-tiptree
My own contribution is a letter „actually addressed to Bulgarian writer Zora Zagorska about Tiptree, which makes for an interesting read“ quoting from one of the goodreads reviewers. My review of her novel The Treasure of Planet Earth can be seen here: http://scifiportal.eu/the-treasure-of-planet-earth-by-zora-zagorska-the-first-bulgarian-science-fiction-novel-written-by-a-woman/ Interestingly, this is the first Bulgarian science fiction novel, written by a woman.
I have to add that participating in this project was very interesting and gratifying, and made me look at our own Bulgarian genre heritage in a very different way, through the prism of the modern gender relations. Unfortunately, the Bulgarian Science fiction (see my historical overview of the genre in Bulgaria at http://scifiportal.eu/between-a-hummer-and-a-rock-the-bulgarian-science-fiction-between-the-east-and-the-west/) is has only rarely made excursions into the English reading world. For some recent examples see:
It is a personal quest of mine to popularize the Bulgarian speculative fiction abroad: