Bloomsbury Auctions in London has 21 lots of Nabokov books (many inscribed) and a lot of 30 letters coming up for sale on 27 November. Go to bloomsburyauctions.com and click on the "Important Books & Manuscripts" auction. The Nabokov lots are #133–154. (Or click here to go directly to the catalog page where the Nabokov lots begin.)
The estimated prices are accurate. The conditions of some of the books are, from the fastidious collector's point of view, not very good. Many copies are not in their original bindings. But there are many desirable pieces. I think that the most delightfully desirable is lot #148, Stikhotvoreniia [Poems] 1929–1951 (A27.1 in my bibliography), published in Paris by Rifma in 1952. The book itself contains 16 Russian poems in a compact 48 pages. The real attraction is the quickly sketched flutter of seven giddy butterflies over Nabokov's inscription to Jacob Frumkin. Take a look.