forums: martha pullen phorum
quilters review
sewforum
equilter (also home to a library which includes this discussion on puckering).

flickr: quilts and quilting

misc quilting links: handy info on various things to consider from quiltville including thread colour choice and pieced backings (plus lots else to browse).
batting faq
standard quilt measurements
looooads of info at victoriana quilt designs
press your seams open
starching
hand piecing
cutting - grain lines
piecing sharp points
hand piecing tips
perfect hand quilting stitch