First off, where are you located?
FWIW if you go into your user profile and set your country, the flag will display beneath your userID. Makes matters so much easer for people to help, and you'll get answers faster as well.
![ThumbsUp :-+](https://www.eevblog.com/forum/Smileys/default/icon_smile_thumbsup.gif.pagespeed.ce._JElyJQqdB.gif)
Regarding sellers, you could check out
Abebooks, and choose a seller according to what's important to you (feedback, cost, location of seller, ...). Depending on your location, Amazon might also be an alternative.
As per which edition to have, there's material in each that's not in the other, so it's best to get both (check out the table of contents of both editions on Amazon for an idea of the differences).