I’ve posted two 29" rims on eBay, bids starting at 99c.
Rhyno Lite 29"/700c Rim, 36h Black - New
http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=160421664405
Kris Holm 29"/700c Rim, 36h Black, 38mm Wide - Used (just!)
http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=160421665761