To store a file at AWS S3 you will need to make HTTP requests to AWS. One way is using the http object for ASP from Chilkat.
I found this code here (which is untested!) but illustrates nicely the principle behind it:
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body>
<%
' Create http object
set http = Server.CreateObject("Chilkat_9_5_0.Http")
success = http.UnlockComponent("Anything for 30-day trial")
If (success <> 1) Then
Response.Write "<pre>" & Server.HTMLEncode( http.LastErrorText) & "</pre>"
End If
' Insert your access key here:
http.AwsAccessKey = "ABQXXABC83ABCDEFVQXX"
' Insert your secret key here:
http.AwsSecretKey = "XXXXYYYYabcdABCD12345678xxxxyyyyzzzz"
bucketName = "yourbucket"
objectName = "mypicture.jpg"
localFilePath = "mypicture.jpg"
contentType = "image/jpg"
success = http.S3_UploadFile(localFilePath,contentType,bucketName,objectName)
If (success <> 1) Then
Response.Write "<pre>" & Server.HTMLEncode( http.LastErrorText) & "</pre>"
Else
Response.Write "<pre>" & Server.HTMLEncode( "File uploaded.") & "</pre>"
End If
%>
</body>
</html>
Hope this helps you to get on the right track - Good luck!