There are several sites that have experienced users ready to answer your
questions on any php issue - I think that
http://www.codewalkers.com is the
best. Tutorials, hundreds (if not thousands) of registered users, and a very
friendly learning environment.
As for texts, you could try "PHP Essentials, 2nd Edition" by Julie C. Meloni
Note that PHP 5 has a much improved object model, but many ISPs are
reluctant to make the switch, in spite of it's advantages (probably because
they are concerned that old code will fail and there will be a customer
service tornado).
ECRIA
http://www.ecria.com