----- Post your favorite Winter Sowing Sites here!----
The site I learned best from was created by Trudi Davidoff. Her site is Wintersown.org

http://www.wintersown.org/wseo1/How_to_Winter_Sow.html

Good lists of Annuals and Perennials that can be winter sown.
http://faq.gardenweb.com/discussions/2766877/hardy-annuals-for-winter-sowing

and
http://faq.gardenweb.com/discussions/2766864/common-flower-garden-perennials-for-winter-sowing-zones-included

This is what I do all year long: Collect lots of clear or opaque 2 and 3 litre soda bottles and quart and gallon milk jugs. Clean and cut them for planting.
I have 2 diagrams with instructions for cutting containers on my Winter Sow Ideabook, here on Houzz. Click on my profile to get there or go here:
http://www.houzz.com/ideabooks/44267068/thumbs/winter-sowing

Houzz has the Winter Sowing Forum where people are posting questions and answers that are helpful:
http://forums2.gardenweb.com/forums/wtrsow

Some good articles to read about winter sowing from Davesgarden.com are:
Winter Sowing - General Questions - http://davesgarden.com/community/forums/p.php?pid=1092565

Six More Weeks of Winter!? Celebrate by Winter Sowing Your Seeds! Article by critterologist
http://davesgarden.com/guides/articles/view/585/