Students are asked to bring their novel to class every day during the unit for which it has been assigned. Students will be annotating their texts, but this by no means precludes the use of a used or library copy; annotation ("SUBSEARCHING") can be accomplished using Post-It notes. Electronic copies of the texts above are also perfectly acceptable, whether on a phone or e-reader (Kindle, iPad, etc.). Sometimes, pdf versions can be found online for free.
All of these texts will be available for purchase in the school bookstore (at or below new book pricing on Amazon), but availability is contingent upon student demand. If you intend intend to purchase his or her book from the school bookstore, it is suggested that you do so early in the year, preordering at registration if possible. Please secure your texts in the manner that is easiest and most economical for your family.
The publisher and edition is relatively unimportant unless it's a work in translation (Oedipus and Antigone). As long as the text is unabridged, the pagination may be different, but the content will be the same. To supplement your reading, audio versions are often available online (iTunes store or similar, or sometimes free on YouTube) or through the New Lenox Public Library. Consider adding an audio version if you have a long trip coming up, travel to or from a game, etc.