h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Okay, your instructions were clear enough, but I'm not sure if I've got a first edition/first printing or not. The book, on the inside, says

"First Printing, December 2003
1 2 3 4 5 6 7 8 9"

Does that mean I've got a first printing/first edition book?

What does it mean if the lowest number in the string is a 0?

I'm guessing that it's first edition because of the 1, but it gives the date of the first printing which could also mean it's second printing.

Still confused.

Books always (I think) have the year the book in question was printed, so if the book doesn't have another (later or same) year printed somewhere on the same page, "First Printing, December 2003" quite propably means to say "out loud" that the book in question is a first print (and was printed December 2003).
(I do hope this makes things clearer, not more confusing :P )

Uncorrected proof copies are also worth sometihng. A proof is a printing of a book before it reaches publication and are generally given out to reviewers, booksellers and of course, proofreaders to read before it reaches the shops. I sold a proof copy of Vernon God Little, last year's Man Booker prize winner for £75 earlier this year, and that was a bargain!