A number of people have asked in the shop or sent us messages online asking about seaming up the 2009 afghan squares. We have good news and bad news... the good news is that seaming, while time consuming, is very easy. The bad news is that there are about a million ways to do it (okay, really more like four or five) and the technique that we recommend is the one that works best for you personally. There is not one "right way" that we can tell you - as with most things it's not a question of right or wrong (although I suppose using a technique that didn't hold the squares together technically would be "wrong") it is more a question of more effective vs. less effective. What works best for you.
Knitty.com, the font of all knowledge, has an excellent article on seaming here, and we recommend you read it whether you decide to use this technique or not - it can still help you in other projects.
The forums on KnittingHelp.com also has a thread with a lot of links to a lot of other tutorials here. It's two pages and may take while to get through, but there's a lot of links to helpful information there.
Also, if you're on Ravelry, there are a couple of threads which talk about the pros and cons of the different techniques here and here.
Why haven't you started seaming your squares yet?
Well... because my first six squares (Jan - March; I'm doing two of each) look like this:
As you can see, they're almost all different sizes. What I plan to do is wait until I am done knitting every square I want for my afghan, and then crocheting a border around each of the smaller ones, bringing them to the same size as whichever square turns out to be the largest. I haven't started on this yet as ... well, who knows? My December square may turn out to be the largest of all, and I don't want to have to keep coming back and crocheting on more edging. I'd rather wait until the end. That's my decision - your mileage may vary!