Here's some additional thoughts I have.
* It should not be underestimated that you (= anyone) can find a lot of info on where to find certain (sensitive) species. Tools like Google Earth etc. make it more easy to deduce a lot from seemingly harmless habitat shots. This somehow makes it "less terrible" to give information to other people? Maybe, but each time sensitive info gets to the wrong people is one time too many. In other words, in my opinion it's not because evil-hearted poachers can already find out a lot by intellegently using the internet that I should add to that. Apart from that, I think we should try to be smart when intending to being vague.
* I admire Rok's DIY perspective, but I would not really want to do 10 visits to the same place and I am a filthy twitcher, so I "need" to find it all and preferably all in one trip
. Yes, you can find most species yourself with enough time and dedication, but there are a few species that require A LOT of dedication. As examples, I would imagine that you could spend years looking for Euproctus platycephalus or Alytes muletensis. Snake-wise there might less such species, although I think if you only know the habitat description plus a European distribution map of ursinii, you could also enjoy years of frustration . To find the Pyrenean rock lizards, you might also be on it for a while, if you only have global maps. It's not surprising that the hard-to-find ones are those that I'm asked for most often, I guess.