I do this, and I don't really bother with using an SSL connection because my documents are not exactly that private. I do use a password protected directory though.
Here is one method in a general form.
www.hotscripts.com has tons of scripts, one of them should be free and good for your purposes. I would suggest looking in the PHP directory, if you need help finding a specific one, or installing a php file just ask.
Then I believe that you should make a directory for this uploading script which is password protected. The upload script you should look for will have something, if you can't find one there are some simple password scripts too.
Then to force it to do SSL your pages should have this PHP script at the top of them all.
Code:
if($_SERVER["HTTPS"] != "on") {
$newurl = "https://" . $_SERVER["SERVER_NAME"] . $_SERVER["REQUEST_URI"];
header("Location: $newurl");
exit();
}
Its not that tall of an order actually, it just takes a little direction.