The Bonus disc of the 2006 DVD release is a version of Star Wars, pre-ANH. Around these parts it's referred to as GOUT. (George's Original Unaltered Trilogy) They can be purchased from ebay or maybe some other online outfits like amazon.

http://www.amazon.com/Star-Wars-Two-Disc-Widescreen-Theatrical/dp/B000FQJAIW/ref=sr_1_1?ie=UTF8&qid=1341003919&sr=8-1&keywords=star+wars+2006

Otherwise LaserDisc is still, to som,e a viable format, but those will all be used, but still will be less tinkered with.

After that is fan created preservations. Please read:

http://originaltrilogy.com/forum/topic.cfm/Notes-on-Piracy-Please-Read/forum/17/topic/13347/

and

http://originaltrilogy.com/forum/topic.cfm/Fan-edit-preservation-forum-rules-and-FAQ/forum/17/topic/5950/

Before reading the rest of that section of these forums.