Abcteach is a one-stop source for all your worksheet/printables needs. There are thousands of free printables available to anyone and more than 35,000 items available to those who sign up as members ($40 per year). I received a short term membership for the purposes of completing this review.
I have to confess, we are not really a worksheet family. Unless I'm forcing my Schnickelfritz to practice handwriting, he'd much rather build things than put pencil to paper. I'm of a mindset that wordsearches and coloring pages are just busy work to keep one student occupied while the teacher is working with another student. Since I only have one child, this isn't necessary. I did explore some of the content reserved for members only to see if membership would be of value to other homeschoolers.
The biggest membership advantage seems to be the abctools--wizards to help you create customized worksheets. If you are a unit sutdy or lapbooking family you can generate crossword puzzles, word searches, and shape books that fit your current study theme. I did try the handwriting tool to make practice sheets for Fritz. We use Handwriting Without Tears which is one of the available fonts. You can fit three very short sentences on a page. My third sentence "I play with my dog" was too long and carried over to a second page so it could be a paper waster.
I also tried using the extensive clip art library to make a food chain project (you'll hear more about that in another review). I was searching for pictures of common animals -- squirrels, owls, deer, etc. I got frustrated with the amount of time it was taking to try and locate each animal. There are subtopics in the clip art library for animals of North America, South America, etc., but they did not include all the animals. Another subtopic was "Mammals" but the listings within the topic were not alphabetical so I had to look through several pages each time. When I tried typing specific names in the search engine I had to dig through listings for word searches and puzzles to find the clip art. When I did get to the picture I wanted, it could be copied and pasted into my word processor, but it was often way too big (filling the page and pushing everthing else offscreen).
My best advice to you is to try abcteach for yourself. By browsing the categories or using the search engine, you can see what items are available for free and what items are available for members only. You can even try the abctools to customize some worksheets in a limited way (only a sampling of formats or limited themes, etc). If worksheets are something your students enjoy, then by all means sign up--the $40 will go much further here than if you tried to buy workbooks for each subject for each student.
You can read what my fellow crewmates thought of abcteach by clicking here.