A few of my favorites are via Layla Grayce, such as this "songbird" apron (pictured right). 100% cotton, machine washable. It is $22, which, to me, seems reasonable enough for an apron. I also enjoy the "french toile" apron ($22) and the "hostess" apron in onyx ($29), which, apparently, was featured on Oprah.
Anthropologie also carries aprons, such as this waterleaf half apron (pictured left). I think this half apron would look especially nice with dark jeans . . . although, you're cooking, and I believe matching while cooking isn't all that necessary. Made from 100% cotton; the apron is $24. It matches the waterleaf mitt and waterleaf potholder, $10 each, available here.