http://www.abcteach.com/ This has a lot of stuff for free and more if you chose to become a member. I'm not a member of this one and still find some great things.
http://oldfashionededucation.com/ This is actually a free curriculum that uses a lot of public domain sorces which keep it free. It's Christian based and using a Charlotte Mason approach for the most part.
http://www.letteroftheweek.com/ Brightly Beaming Resources is the curriculum I used as a spring board for Micki's preschool year. It actually starts with a curriculum for babies!
http://www.edhelper.com/ A lot of resources including the ability to make your own word search and crosswords puzzles.
http://enchantedlearning.com/ Really like this site. I even purchased a membership for this one because it was fairly reasonable and many of the things you can access as a member can be saved which means I'll be able to get them later when I'm no longer a member.
http://www.homeschoolhelperonline.com/index.htm This site has unit studies, as well as, FIAR and lapbooking resources.
http://www.kitzkikz.com/flashcards/ Make your own flashcard resource
http://picturedots.com/view/viewAll.php Kind of a cool site with various dot to dots already made and the ability to make your own. This is not your old-fashioned dot to dots. There are dot to dots of things like a motorcross helmet, Eiffel Tower, the outline of Ethiopia, etc. Some as as many as 400+ dots!
http://www.gardenofpraise.com/index.htm It has a lot of different subjects from Bible lessons to famous art work.
http://www.kidzone.ws/ A lot of worksheets for various topics and grades.
http://www.preschoolexpress.com/ Another great source for PK and K items. Some could even be expanded for older students.
http://www.worksheetworks.com/ Puzzle pre-made and make your own as well as other worksheets
http://www.teacherhelp.org/color.htm#bible Has links to a lot of various Bible topics
http://children.calvarychapel.com/site/curriculum.htm A great resource for teaching through the Bible. I'm currently using them as the outline for our Bible lessons.
http://gamequarium.org/ Computer games for various ages and subjects.
http://www.starfall.com/ I have yet to come across a child that doesn't like Starfall. Helps teach reading skill with phonics and also has other things like making your own monthly calendar and learning about famous composers.