Well I have known of people flying with a road atlas, and in a lot of places you will get away with that
What you get in a Bottlang guide is all the VFR plates i.e. approach diagrams, required VRPs, contact numbers (which are often duff because Jepp don't dial any of them), and other VFR-useful stuff.
You can get the same stuff from the relevant national AIP, but not all of these are published online (Greece being one) and also it is not really practical to print out the AIP for all of say Greece but the Bottlang guide for Greece is one fairly portable Pooleys-guide-sized thingy. OTOH if you are definitely visiting only 1 or 2 places then printing out the AIP is fine.
Try to have a look at the EAD site. It's a typical crap piece of web design where somebody got paid for a fancy job. It downloads several tens of MB of java objects. Eventually you click on Enter, and to get the bit you want you click on "Pams Light" (yes you knew that really). Eventually a fairly obvious form appears and you can view the various AIPs, approach plates, etc.
There is also a link to some national AIP websites
here.