A lot of people order picture cards for Christmas. They actually are pretty cheap and easy - all the writing is already on them so if you don't feel like adding anything else, just pop them in the envelope and send them on their way!
How can you make this less stressful? For starters, order them NOW! Your kids aren't going to grow that much from October to December. Just take the picture and order the cards. If you order from Snapfish before October 31st, you can score free shipping with code SLIMSHIP.
Have you been doing the Pampers Gifts-To-Grow program? Check your point balance - you can get 25 4X8 cards from Shutterfly with only 60 points. I've been a member since 2005 - but I stopped buying Pampers about a year ago. I have 274 points banked. If you buy Pampers exclusively, it would def. be a great program for you to join.
I remember last year, a few of the companies (I think Kodak comes to mind), did a promo in November to score cheap cards. You could have already gotten them with your $15 Kodak Credit last week - but I didn't.