Maternity Wear

This doesn't help for online tutorials, but some of the prettiest, trendy patterns I have seen are Jalie patterns:
http://www.jalie.com/sewingpatterns/maternity.htm

Also, these patterns are in Danish, but there are some really cute and simple maternity clothes patterns here.  You need to be a little more familiar with sewing to use them, because European patterns tend to make a lot of assumptions about the user knowing how to do things, unlike American patterns.  (For example, it would say "make a casing" and not explain how to do that.)  http://www.fjoelner.dk/varegrp.asp?la=uk&uart=50

I havent tried this tutorial yet but I am no longer fitting into my jeans so it about time I tried (24 weeks here!)

http://creativelittledaisy.typepad.com/creative_little_daisy/2007/10/250-maternity-j.html

I'm pregnant too and although I'm not showing yet (10 weeks along!), or will be for another little while, I still want to be prepared! I found that Burda has some cute maternity patterns. I especially like 7800. Unfortunately sometimes the smallest size is 10 (37.5" bust) and so I'll be posting a question about how to shrink a pattern!

Good luck finding what you're looking for. And thanks to everyone for commenting. You're all so helpful!

I'm at 22 weeks myself and am loving sewing my own maternity clothes when I can find fabric.  It seems like all of the ready-to-wear stuff is either super expensive, huge, or has really ugly colors.  I just made myself 2 tops from Butterick 5217.  It's not a maternity pattern, but it's plenty roomy in the places it needs to be roomy in.  I made it 2 sizes bigger than I usually am and I'm pretty sure I'll be able to wear both tops through the rest of my pregnancy.  Right now, I'm just wearing a belt just below my bust since I'm not that big yet.

This is also a super easy pattern and it doesn't take a ton of fabric to make. 

You could also find an empire-waist top pattern in non-maternity wear and alter it pretty easily for the bump. I did a few shirts this way when I was pregnant:

http://www.flickr.com/photos/supamb/436462827/

and this is how i redrew the shirt front:
http://www.flickr.com/photos/supamb/2468438251/in/set-72157594204770081/

Good luck, and congratulations!