crunchyroll or opanime .net
you can watch it at 'dbzepisode.org'
Some of the episodes are on Veoh and on YouTube.
It depends; I do not personally know of sites for dubbed/English episodes; but for subbed Japanese episodes, Dailymotion.com has many subbed episodes, in good quality.
Hulu has the "4kids" version of One Piece on its website. The episodes are dubbed in English and are changed for the younger audience. However, the production of the dubbed episodes is minimal and will have to be viewed subbed eventually. So I recommend that you just watch the show in the original japanese version with the subtitles.
i watch all of my anime on animeseason.com. this site is better than any other that I've used since it give you a selection of player to watch the anime on.
One Piece ,
I personaly go to Watchop.com. I watch subbed (Japanese). They are pretty good at updating there episodes :) They also have dubbed (english), last time i checked they only had that range of episodes up to 200. sorry if i couldnt help.
Try Veoh.com. I go there to watch it subbed. YouTube has quite a few episodes, too, but not all of them.
i'm not sure of a tv channel but you can watch it subbed at animeseason.com along with a big selection of other anime. worth a check its the only place i watch anime now :)
Technically, the movie hasn't yet premiered in English. You can watch it subbed if you Google it, but I'm not exactly sure where. Check the related questions and maybe you'll find it subbed there.
if you watch subbed in English, it comes out online if you look every Friday (late Thursday) For all episodes of Naruto and Naruto Shippuden visit http://naruto.animefi.com You can watch all the episodes there for free.
online, just type fairy tail English but be careful it's not subbed