Everyone else, you still can request a gift.
I have a shelf of random books on cryptozoology I use to draw my own monsters with pen and ink; the "Historie of Four-legged Beasts" by Topsell is sadly missing, but I have the scans of the few pages. Judging from which, he devoted a large portion of his tome to snakes and birds.
"The Lore of Unicorn", by Odell Shepard, Avenel Books, New York. The prototypical book on cryptozoology. You probably know it already. Shepard traces the legend of Unicorn back to Greek writers misunderstanding Persian travelers' tales, to Ctesias and Pliny. He follows the fate of the artifacts known as alicorns through European history. He provides enormous amount of information and hints at more. And he writes well.
"The Book of Imaginary Beings", by J.L.Borges, E.P.Dutton&Co, New York. Maybe, best of Borges. Maybe, second to "Aleph" -- depends on how much of a plot you prefer in your dreams. Fantastic, academic, dry and accurate; Borges chose most culturally important, most traditional and symbolic beast (and some obscure, even fake ones). You see, there are existing non-existing animals and non-existing, completely made up non-existing animals, and the blind librarian (I came to hate U.Eco, by the way) knows the difference.
"Monster, Giants and Little Men from Mars", by Daniel Cohen, Laurel-Leaf Library, Dell Publishing, 1977 -- a small paperback with a reasonable bibliography and index. The book is too entertaining to be accurate, but hey, he is talking about little men from Mars! Most of my librariette deals with traditional (that is, Ancient Eurasian or Medieval) monsters, with characteristic remote and academic feel to it, but this one, brimming with folklore of boy scout leaders and lumberjacks is first-hand lighthearted and scary. Cohen claims that some of the lumberjack monsters are inherited from Indians, so there can be some tradition to his material, as well.
"A Jewish Bestiary", by Mark Podwall, the Jewish Publication Society of America, Philadelphia, 1984. Fifty pages of nicely bound and tastefully illustrated pretentious nonsense. Despite my national sentiment and my reverence to heritage and tradition, and despite Elie Wiesel's endorsement, still pretentious nonsense. Whatever is interesting there is a result of Hellinistic contamination. The general proverbial, moralistic feeling resembles that of the Bysantine Physiolog, but fake and modern.
"A Dictionary of Fabulous Beasts", by Richard Barber and Annie Riches, illustrated by Rosalind Dease, by the Boydell Press, 1971 A nice, well-referenced dictionary, obviously inspired by the Borges' book. Illustrations are line-drawings imitating wood prints, resembling both Topsell and illuminated Medieval Bestiaries in style. One can doubt if Banshees, Devil or Elves belong to a dictionary of beasts, but we do study Men in modern zoology courses.
"The Book of Fabulous Beasts", edited by Joseph Nigg, Oxford University Press, Oxford. A cross of the reference book, a dictionary, a collection of citations. Very useful and deceptively systematic. The classification he uses resembles Borges' classification (the animals belonging to the Lord Emperor... The animals painted with the soft brush... see how Borges keeps reappearing? I wonder why): there are Ancient Animals, splitting into mythic and exotic, Beasts of God (scriptures, fables and allegories), and so on. The material (citations from different sources) is arranged in the chronological order of writing.
"The Book of Dragons and Other Mythical Beasts" by Joseph Nigg, Barron's is an illustrated children's version of the above, with the traces of the same arbitrary, but useful system.
"The Book of Beasts", being a translation from a Latin Bestiary, by T.H.White, G.P. Putnam's Sons, New York. Exactly what it says. Fascinating reading.
"Giants, Monsters and Dragons" by Carol Rose, W.W.Norton&Co, New York A generic encyclopedia, Barnes&Noble-sale style. Very large and so nice to have, probably inaccurate, covers everything from Zmey Gorynich to Quetzalcoatl. Makes no distinction between individual monsters and monster species, which bothers me, but this issue of cryptozoology is murky anyway.
"The Element Encyclopedia of Magical Creatures", by John&Caitlin Matthews, Brnes&Noble, New York. The Barns&Noble $10 hardcover edition, bought it on sale there because I could not pass the book on magical creatures. Imagine a fat cookbook printed by some processed food company. Ten ways to enhance your dinner with our condensed mushroom soup. Something like that. Still, it's a large thing with lots of letters in it. I don't like it but I do use it as a starting point.