Reprinting aperture and iphoto books

Can I reprint either iphoto or aperture books I made several years ago without recreating the book?

Only, if you still have the book project in in your Aperture or iPhoto library. Apple does not store the book that long on its servers; it is kept at most for one month. It needs to be uploaded again for a second printing.

See the Apple Photo Services: Product line details for books, cards, and calendars

You'll need to have a running version of Aperture 3 or iPhoto '09 or '11 installed. If your book has been created with an earlier version, it may change slightly, of you upgrade the library to open it in your current version, because of changed book templates.

No. For future book I suggest you create a separate library just for that book. That will allow the library to be smaller, easily archived by copying to an EHD or a DVD disc for use at a later date. Photos needed for the book can be assembled in an album in your primary library and then copied to the book library.

If the photos are deleted from the master library for any reason they still will be in the book library.