Guidelines:

ATS:
http://www.thoracic.org/sections/publications/statements/index.html

ERS:
http://www.ersnet.org/ers/lr/browse/default.aspx

CHEST:
http://www.chestnet.org/education/guidelines/currentGuidelines.php

BTS:
http://www.brit-thoracic.org.uk/

Journals:

AJRCCM: American Journal of Respiratory and Critical Care Medicine:

http://ajrccm.atsjournals.org/

ERJ: European Respiratory Journal:

http://erj.ersjournals.com/

CHEST: The cardiopulmonary and critical care journal:

http://www.chestjournal.org/

THORAX: An International Journal of Respiratory Medicine

http://thorax.bmj.com/

The International Journal of Tuberculosis and Lung Disease (issued by IUATLD)