I've been working on a similar application and gotten things to work with the following steps:
1. Use RHostResolver (iHostResolver) to convert a servername (http://www.google.com) to an TNameEntry (iHostAddress).
2. Use RSocketServ (iSocketServer) to open an RSocket (iSocket)
iHostResolver.GetByName(serverName, iHostAddress, iStatus);
3. Use a simplet GET command to get the web page. Here you can put a GET or POST and format it as you wish.
iSocket.Open(iSocketServer, KAfInet, KSockStream, KProtocolInetTcp)
4. Read from the socket the data the server sends back.
aRequest.Copy(_L8("GET / HTTP/1.0\r\n\r\n"));
iSocket.Write(aRequest, iStatus); // write the GET/POST request
I think that should be enough to get you started. I haven't done anything more complicated than fetching the google website right now.
iSocket.RecvOneOrMore(iResponseChunk, 0, iStatus, iResponseChunkSizePkg);
I've done this with S60 Feature Pack 2.