So you want to make your current house more efficient?

Some good reading about energy audits & working on existing houses -
http://www.scientificamerican.com/blog/post.cfm?id=before-we-began-a-home-energy-audit-2009-03-02
and
http://www.scientificamerican.com/blog/post.cfm?id=are-old-houses-doomed-the-conflict-2010-03-26

Some Perspectives

http://www.walletpop.com/blog/2010/01/06/cash-for-caulkers-poised-to-return/