Why fiberglass is not the best choice (seems to be ok only for floors):

Blown fibberglass study
Minnesota fiberglass rules update
Fiberglass batts study
University of Colorado-Denver cellulose vs fiberglass in walls insulation study in 1990
Case study of attic wind washing with pictures
More on attic 'wind washing'

Cellulose (cheaper) and foam (most effective) insulation:

Cellulose info
Foam info
Foam insul R-value real examples
Foam fire safety

Other links:

EnergyStar insulation tax credit
Recycled building materials
NH 2003 Green Buildings article