it would be possible to actually fetch their website and extract the date information, but with php code you can actually do the same on your own.
i made this code just now, i am in PST -0800 and it seemed to work fine for me. its not tested at all though so you may want to run some before using it. and note it doesn't handle dst, that'd have to be added but shouldn't be too hard.
<?php
$tz = date("Z"); //timezone offset of server in seconds
$est = 3600 * -5; // -0500 gmt
$cst = 3600 * -6;
$mst = 3600 * -7;
$pst = 3600 * -8;
$hast = 3600 * -10;
// add (or subtract) the appropriate number of seconds from the offset to recalculate the time
echo date("h:i A", strtotime("now +" . ($hast - $tz) . " seconds"));
?>
also, check out the php manual pages on date stuff, there are quite a few comments with functions for doing this stuff. [man]gmdate[/man] has a few on it.