$collection = Mage::getResourceModel('customer/customer_collection')
->addNameToSelect()
->addAttributeToSelect('email')
->addAttributeToSelect('created_at')
->addAttributeToSelect('group_id')
->joinAttribute('billing_street', 'customer_address/street', 'default_billing', null, 'left')
->joinAttribute('billing_postcode', 'customer_address/postcode', 'default_billing', null, 'left')
->joinAttribute('billing_city', 'customer_address/city', 'default_billing', null, 'left')
->joinAttribute('billing_telephone', 'customer_address/telephone', 'default_billing', null, 'left')
->joinAttribute('billing_fax', 'customer_address/fax', 'default_billing', null, 'left')
->joinAttribute('billing_region', 'customer_address/region', 'default_billing', null, 'left')
->joinAttribute('billing_country_code', 'customer_address/country_id', 'default_billing', null, 'left')
->joinAttribute('shipping_street', 'customer_address/street', 'default_shipping', null, 'left')
->joinAttribute('shipping_postcode', 'customer_address/postcode', 'default_shipping', null, 'left')
->joinAttribute('shipping_city', 'customer_address/city', 'default_shipping', null, 'left')
->joinAttribute('shipping_telephone', 'customer_address/telephone', 'default_shipping', null, 'left')
->joinAttribute('shipping_fax', 'customer_address/fax', 'default_shipping', null, 'left')
->joinAttribute('shipping_region', 'customer_address/region', 'default_shipping', null, 'left')
->joinAttribute('shipping_country_code', 'customer_address/country_id', 'default_shipping', null, 'left')
->joinAttribute('taxvat', 'customer/taxvat', 'entity_id', null, 'left');
Or if you want via mysql query:
SELECT ce.*, ea.attribute_code,
CASE ea.backend_type
WHEN 'varchar' THEN ce_varchar.value
WHEN 'int' THEN ce_int.value
WHEN 'text' THEN ce_text.value
WHEN 'decimal' THEN ce_decimal.value
WHEN 'datetime' THEN ce_datetime.value
ELSE NULL
END AS value
FROM customer_entity AS ce
LEFT JOIN eav_attribute AS ea ON ce.entity_type_id = ea.entity_type_id
LEFT JOIN customer_entity_varchar AS ce_varchar ON ce.entity_id = ce_varchar.entity_id AND ea.attribute_id = ce_varchar.attribute_id AND ea.backend_type = 'varchar'
LEFT JOIN customer_entity_int AS ce_int ON ce.entity_id = ce_int.entity_id AND ea.attribute_id = ce_int.attribute_id AND ea.backend_type = 'int'
LEFT JOIN customer_entity_text AS ce_text ON ce.entity_id = ce_text.entity_id AND ea.attribute_id = ce_text.attribute_id AND ea.backend_type = 'text'
LEFT JOIN customer_entity_decimal AS ce_decimal ON ce.entity_id = ce_decimal.entity_id AND ea.attribute_id = ce_decimal.attribute_id AND ea.backend_type = 'decimal'
LEFT JOIN customer_entity_datetime AS ce_datetime ON ce.entity_id = ce_datetime.entity_id AND ea.attribute_id = ce_datetime.attribute_id AND ea.backend_type = 'datetime'