A query request is simply an HTTP GET request that returns XML.
Here is a request that looks up traffic rank data for yahoo.com:
http://awis.amazonaws.com/?
AWSAccessKeyId=9876543212345123
&Action=UrlInfo
&ResponseGroup=Rank
&SignatureMethod=HmacSHA1
&SignatureVersion=2
&Timestamp=2011-05-06T17%3A58%3A49.463Z
&Url=yahoo.com
&Signature=Wz2UT%2BtCYZghLBmqtkfEpg%2FqrK8%3D
See Common Request Parameters and Actions for descriptions of query parameters.
The Signature parameter is used to authenticate the request. It is calculated as the hash of the request's "string to sign" as described in Calculating Signatures. For the sample request above, the string to sign is:
GET\n
awis.amazonaws.com\n
/\n
AWSAccessKeyId=9876543212345123&Action=UrlInfo&ResponseGroup=Rank
&SignatureMethod=HmacSHA1&SignatureVersion=2
&Timestamp=2011-05-06T17%3A58%3A49.463Z&Url=yahoo.com
where \n represents a newline. The last three lines are actually a single line, with no newlines.