Hi, karim2k. I wasn't meaning to be dismissive, but merely stating a fact. I'm actually trying to save you some time .
I have browsed all posqtgresql main site links , but I'm asking for further links !
Really? You have browsed all PostgreSQL links? There are hundreds of them. I have been using PostgreSQL for years, and I still haven't managed to read everything in those links.
Seriously, you're not going to find any better information than what you find in the *.postgresql.org sites. I have searched the web, and everything useful that I have found ends up being linked back at least to techdocs.postgresql.org, if not mentioned all through http://archives.postgresql.org/
PostgreSQL has what I consider to be the most cohesive community of any open source project. Everyone involved tends to submit their best info back to the main sites.
I do have a couple odd links for you that don't appear in the PostgreSQL sites, but nothing major:
In my opinion, anyone wanting a real education on PostgreSQL should just start reading through the mailing list archives, or at least subscribe to the pgsql-general and pgsql-sql mailing lists. It doesn't get any better than this, since the core developers take time to answer so many questions.
Otherwise, if you are interested in creating a nicely organized, searchable list of links for PostgreSQL information, that would be a Good Thing, but it would mainly involve re-organizing the information that is already available.