I don't know if you saw it but I posted a message on llbean knit pants. You can go to their site and do a search in the women's knit pants area for drawstring or elastic. These pants provide a sporty casual look.
What I didn't mention before is that you can also use the virtual model on their site....eventhough that made me a bit depressed because I put in my large waist line size when I bloat up...but it gave me an idea how it would fit on me and whether or not I should purchase it.
You might also check out Lands End they also have a strech knit with elastic selection.