You can't buy literary success, but if you have a little more than $5 million, it may help you gain insight into the minds of two of the greatest 20th-century novelists.

That's how much it would take to buy two collection of letters currently up for sale by a prestigious New York dealer in literary artifacts. A correspondence between "On the Road" author Jack Kerouac and his college friend, is priced at $1.25 million. What amounts to a biography in letters by and to the British novelist Virginia Woolf is for sale at $4 million. Both are being offered by Glenn Horowitz Bookseller in lower Manhattan.

The Kerouac collection includes 59 letters and postcards, part of the author's correspondence with his friend Ed White, whom he met while the two were students at Columbia University. The letters span from July 1947, when Kerouac started the travels he documented in his novel, "On the Road," until two months before his death in 1969.

"Kerouac had a phobia, might be too strong of a word, but he had an antipathy to the telephone and there were a handful of people… with whom he carried on long dialogues through letters," said Glenn Horowitz, president of the firm selling the collection.

White's influence on Kerouac's erractic, impressionistic style is obvious, according to Horowitz. "It's White who Kerouac credits with having introduced the idea of sketching with words as a way of trying to somehow capture the impressions that were swirling in his consciousness. That sketching is what really evolved into the prose style that we now associate today so intimately with 'On the Road'," said Horowitz.

One key letter to White is written on the back of a page belonging to an early manuscript of "On the Road." "The most poignant and interesting letter is from the late '40s," Horowitz explained, "in which [Kerouac] talks about the onset of the composition of 'On the Road', and really what's wonderful is he's written on the back of a manuscript leaf for a very early iteration of [the novel]."

The value for this letter alone is estimated at $100,000, but Horowitz is only selling it as part of the collection.

While the Kerouac collection offers insights into the origins of his writing style, the Virginia Woolf letters offers fans a glimpse of her personality and life. Many are written to Woolf's nephew Julian Bell, who was killed at a very young age in the Spanish Civil War, fighting for the loyalists. Others are from family -- Leonard Woolf, her widower, and Vanessa Bell, her sister.

The most poignant, said Horowitz, is one written by Vita Sackville-West, Woolf's lover, describing Woolf's suicide and the days leading up to the discovery of her body. "It's really one of the most touching collections of letters I've had the privilege of handling," Horowitz said.

"She was able to express all of the dimensions of her personality. The one that is oftentimes lost when people think of Virginia Wolf is this great sense of playfulness and humor that animated the perspective that she had on the world," said Horowitz.

Besides the insight, part of what makes the Woolf collection worth millions is how it was put together.

"It was put together piece by piece, to sort of reflect the vision that the collector had of his intimate response and connection to Virginia and the intervention she had in his life over the course of building this collection," Horowitz explained.