doing some reserch I found that the website for the book "Battlefield Earth" has a Quote that is attributed to Neil.
"Over 1,000 pages of thrills, spills, vicious aliens and noble humans. I found Battlefield Earth un-put-downable.
Neil Gaiman"
http://www.battlefieldearth.com/00v4/acclaim.htm
http://en.wikipedia.org/wiki/Battlefield_Earth_%28novel%29

Now I have my personal opinions about the book, but that just dosn't sound like somthing he would have said, the tone seems different from his usual statements.

does anyone have a source for what he actually said?

He's done two reviews for "Battlefield Earth" -- One in Imagine magazine #29 and one in Space Voyager #16.

I don't own these magazines, but I know who does and will ask if he can look them up.

edit: "Un-put-downable", though, sounds like pure Neil.

That quote is from the Imagine magazine that Aitapata linked to. "Neil Gaiman, author of Imagine short stories Featherquest and How To Sell The Ponti Bridge, and co-author of Ghastly Beyond Belief, reviews the latest additions to the fantasy/SF media."
Full text of that review:
"For value for money I have to recommend L. Ron Hubbard's massive Battlefield Earth - over 1000 pages of thrills, spills, vicious aliens, noble humans. Is mankind an endangered species? Will handsome and heroic Jonny Goodboy Tyler win Earth back from the nine-foot-high Psychlos? A tribute to the days of Pulp, I found it un-put-downable. And all for 2.95"(Brit currency)

That's from a column published August 1985. Also reviewed in that issue, to give a sense of age, Night Of The Comet and Cat's Eye.

Ooooh boy, his main description was as co-author of "Ghastly Beyond Belief"? That's pretty old (and funny).

quote:

Originally posted by coffeepusher:
"...I found Battlefield Earth un-put-downable.
Neil Gaiman"

Everyone gets one mulligan.

And, honestly, he's saying Battlefield: Earth is pulp science fiction, which is exactly what it is. And, judged only against other pulp fiction, it's pretty darned good