In case you hadn't stumbled across it http://www.hammockforums.net/links/browselinks.php?c=9
has links for some of the suppliers forum members have used/know about. Also, scroll down a bit here http://www.specialtyoutdoors.com/tips/sources.asp
for Canadian fabric sources.
Being a tactile person myself, perhaps ordering a set of fabric swatches from one of them may also be helpful?