Want to create a Question/ Answer site, So what should I read to build such a site?

It's impossible to answer all your questions in one answer.

If you're really new to php, I doub't you should dive in a CMS.

I recomend you to split-up your questions in to smaller ones and start googling and coding.

• People should ble able to post
  • Choosing a database?
  • Adding entries to a table?
  • Registering users?
• Commenting
  • Again, adding to database
  • Retreiving from database
  • Displaying results
• Categories
  • Database architecture
  • Normalazing database
  • Again, adding and retreivieng from database

..and so on.

This would be ok if you're doing it for practice, not for real life product.

If you're looking for a quality product, you should go for a cms.

There are several open-source packages you could use. Or you could go over to http://area51.stackexchange.com/ and see if any of the 566 sites in development would do what you want.

Some open-source question-and-answer packages:

• OSQA - http://www.osqa.net/ (Django / Python)
• AskBot - http://askbot.org/ (Django / Python)
• Shapado - http://shapado.com/ (Ruby/Rails)
• Question2Answer - (see that dot org)- (PHP)

OSQA is open source stackoverflow.com clone, running on Django and Python

http://www.osqa.net/

(just replace one P in your LAMP stack with another P :)