I would try ebay first, but if you want something new, probably TJ Maxx, Ross dress for less, or Marshall's would probably have something of good quality for cheap.
Landsend catalog will ship the item free to your closest Sears, so you don't have to pay shipping costs. You can also return Landsend to Sears, no shipping costs. Landsend is a bit pricey but they have great sales. Very high quality and good fit.
(Now what lucky person gets to iron those 100% cotton shirts?)
I hate ironing, but I love the feel of a crisp cotton blouse or preferably cotton and polyester blend. Knits pill, don't look nice after one season and show all my sins. LOL