The Importance of Dust Jackets
I modify the well-known real estate business phrase, "location, location, location ", to stress to beginning book collectors, "dust jacket, dust jacket, dust jacket ". Its that important to the value of your books!
To say that up to 90% of the value of a collectible first edition is in the dust jacket is not an exaggeration. Why? The purpose of the dust jacket (or dust wrapper) is to protect the book from wear. So it was originally intended to be 'disposable' for lack of a better term. Things that are disposable tend not to last, so there aren't as many of them around. The law of supply and demand takes effect, and scarce items become more valuable.
An example: A copy of Anne Rice's "Interview with the Vampire", first edition 1976 WITH a VG+ dust jacket can command a $600 to $800 selling price, up to $1000 for one with a fine dust wrapper. The wrapper is gold foil, and shows any crinkle or fold, so an as-new quality dust jacket is quite scarce. The same book without a wrapper ... $60. You will find this type of price variation to be the case for any book. A dust wrapper in nice condition increases the value of your book tremendously over one without a jacket.
ARCHIVE your dust jackets: So protect those dust jackets! I advise using mylar, archival protectors. They are available singly or in packs of 3 at local book stores, but my primary source for them is Gaylord Brothers in Syracuse, NY.
Personally, I buy rolls of mylar protector sheet stock made for books 14 1/2" to 16" high (item #R16) and trim as needed to fit any size of book smaller than that. That way I only have to stock one size of roll. Gaylord will sell to private individuals and will take credit card orders over the phone or by internet. With your shipment, you will also receive a current catalog.