Cisco Valet AM10 Connector Wireless USB Adapter for $6.99. Shipping is $5.00 for a total of $11.99 shipped.  Here is a screenshot for your reference.  It is complies with 802.11b and 802.11g standards and supports WEP (64- and 128-bit), WPA and WPA2 encryption.  Most places have this wireless adapter for about $27 or more.