Hi Sandeep:
Learning about a technology like PHP spans three levels.
Level 1: getting comfortable with syntax and configuration
writing simple pages.
debugging
Level 2: implementing modules,
multi-page interactions,
programming idioms
debugging
Level 3: utilizing system services,
writing extensions
advanced programming idioms
code refactoring
Here is one possible set of books to take a look at
Level 1: Beginning PHP
Level 2: PHP Cookbook
Level 3: study PECL, PEAR code
study one product like wordpress or drupal
At all times, you must consult the online PHP documentation at
http://www.php.net/manual/en/
The online documentation is "invaluable" as it is 'annotated' !
>From an effort perspective,
Level 1: 3 weeks (max)
Level 2: 9 weeks (max)
Level 3: 21 weeks(max)
Writing code is going to make a 'lot of difference' !
Please let us know if you have any more questions.
thanks
Saifi.