Is this website, http://www.theepochtimes.com, a reliable souce of
news in China? Are the articles written by the site trustworthy or
not?

Nope.  I believe it;s publich by Fulan Gong.

Let's try that again:

Nope.  I believe it's published by Fulan Gong.

Yes, it is apparently closely related to Falun Gong.  Scroll down to page 218
on this site:
http://www.sfu.ca/cmns/faculty/zhao/14_03-168_Ch13.pdf

From 
http://www.sfgate.com/cgi-bin/article.cgi?file=/c/a/2005/12/18/MNGGAG8MTA1.DTL
---
Orville Schell, dean of the UC Berkeley Graduate School of Journalism
and a China expert, said these outlets might boost their credibility
if they addressed China's undeniable economic boom and the staying
power of the Communist Party. But he said that omission isn't a fatal
flaw.

"They are a manifestly dissident voice and don't pretend to be
otherwise," said Schell. "It's hard to vouch for their quality because
it's difficult to corroborate. But it's not something to be dismissed
as pure propaganda. It is covering an aspect of China, which other
publications cover much less aggressively."
---

See also 
http://en.wikipedia.org/wiki/The_Epoch_Times#Focus.