The game site I don't know, but the official site is: http://harrypotter.warnerbros.com/harrypotterandthehalf-bloodprince/
azkaban
one can find about harry potter's life on wikipedia or potter lexicon or on rowlings official site.
Some good sites for Harry Potter news and entertainment are fansites like Mugglenet and Leaky Cauldron. The best site overall for Harry Potter is Pottermore, an official Harry Potter experience. It opens to all in October.
No, there is only one WikiAnswers site however there are many categories for the Harry Potter series on the WikiAnswers site. There is however, a Harry Potter a wikia.
I don't know if there is a site for that book, but there is a site that has Harry Potter games, stories, jokes. recipies, and videos. It is called Mugglenet.com.
Most places that sell lego sets will sell the Harry Potter sets. Among these are Walmart, Sears, and Toys R Us. The official Harry Potter site is also sure to have the sets as well.
Can be found through Warner Bros official site. Search Google for HP HBP Trailer and you'll find it.
No, filming is over. There was a competition on the official Order of the Phoenix site to see a day of filming.
All of the Harry Potter book products can be bought directly from the Pottermore website. This is a site owned by JK Rowling, and is the only place to get some of the official items legally.
Only J.K Rowling's and the Warner Brothers site. They aren't really fan sites, more informative.
There is a contest where you upload a video to a site, about Harry Potter, so it was held everywhere.
SnitchSeeker is a web site devoted to fans of Harry Potter. The web site offers the latest news about all of the Harry Potter movies, the actors of the Harry Potter movies, and J. K. Rowling (the author of the Harry Potter books).