A quick post to show how one can easily implement a findByField wrapper in Zend_Db_Table:

/**
         * Implements a simple findByField wrapper
         */

        public function __call($method, $args) {
                if (preg_match('/^findBy([a-zA-Z0-9]+)$/', $method, $parts)) {
                        $field = strtolower(preg_replace('/([a-z])([A-Z])/', '$1_$2', $parts[1]));
                        if (!in_array($field, $this->_cols)) {
                                throw new Zend_Db_Table_Exception(sprintf('\'%s\' field not in row', $field));
                        } else {
                                $db = $this->getAdapter();
                                $where = $db->quoteInto($db->quoteIdentifier($field).' = ?', $args[0]);
                                return $this->fetchAll($where);
                        }
                }
        }

What it does is basically trapping any non-existant method call and check if the corresponding field exists, after converting CamelCasing to underscore_notation (eg: FooBar becomes foo_bar).