This questions is quite related to this one: http://www.question2answer.org/qa/37836/how-can-i-display-users-full-name
The answer is essantially the same. Open the qa-include/qa-app-format.php file and try this code. Green lines are the new added ones:
if (isset($postuserid) && isset($usershtml[$postuserid])) {
$whohtml=$usershtml[$postuserid];
if ($microformats)
$whohtml='<span class="vcard author">'.$whohtml.'</span>';
$userprofile = qa_db_select_with_pending(qa_db_user_profile_selectspec($postuserid, true));
if (isset($userprofile['website']) && !empty($userprofile['website'])) {
$whohtml .= ' Website: ' . qa_html($userprofile['website']);
}
} else {
Of course, you can add a link instead of just the text but in your case you just seem to want the text.
Regarding performance, the explanation is simple: this will run a quick query each time the information is requested (the query is needed even if the user has not set a website in their profile). This means if you have a question list with 20 questions then this query will be run 20 times.
As I mentioned in the other question, this can be improved with a plugin so that it runs only one time per question list. However, that's more complex and not actually suitable for an answer but rather a tutorial targeted to users that know about PHP.
Conclusion, give it a try. I bet you won't notice anything... unless you have around 100 users browsing a question list page at the same time :)
