Have you looked at Webs (
http://yarn.com )? You can do a search there by weight and find some nice colors. Their Valley Yarns 2/14 Alpaca Silk hand-dyed has some pretty colors.
Or, consider doing the Triple Mohair Triangle Shawl from Fiddle Sticks Knitting (
http://www.fiddlesticksknitting.com/TripleLarge.html ). You can use different colors to get the look you want. For example, you could pair this green
http://cgi.ebay.com/Filatura-di-Cros...QQcmdZViewItem with this dark purple
http://cgi.ebay.com/ROWAN-Kidsilk-Ni...QQcmdZViewItem and this lighter blue
http://cgi.ebay.com/ROWAN-Kidsilk-Ha...QQcmdZViewItem to pull together the colors. Or you could stick with three shades of purple, if you wanted to. It's fun to play with the colors in this shawl.