How to consume a web service from VB6?

Assuming that you're running on Windows XP Professional or above, one interesting method is to use the SOAP moniker. Here's an example, lifted from some MSDN page. I don't know if this particular service works, but you get the idea...

   set SoapObj = GetObject
       ("soap:wsdl=http://www.xmethods.net/sd/TemperatureService.wsdl")
   WScript.Echo "Fairbanks Temperature = " & SoapObj.getTemp("99707")

This mechanism also works from VBScript. Which is nice.

.NET has a good support for Web Services since day one, so you can develop your Web Service client logic in .NET as a .dll library/assembly and use it in VB6 app via COM Interop.

I use this function to get data from a web service.

Private Function HttpGetRequest(url As String) As DOMDocument
    Dim req As XMLHTTP60
    Set req = New XMLHTTP60
    req.Open "GET", url, False
    req.send ""

    Dim resp As DOMDocument
    If req.responseText <> vbNullString Then
        Set resp = New DOMDocument60
        resp.loadXML req.responseText
    Else
        Set resp = req.responseXML
    End If
    Set HttpGetRequest = resp
End Function