I'd like to be able to make an HTTP request on the web to a specific server from my Arduino. I already have a Wireless SD Shield, and I am wondering if what I want to do is possible / what I would need to buy to make it work. From what I understand, I can plug an "add-on" shield to that with an antenna, like an XBee Wireless Transmitter. However, all examples I find on the web of such things use two Arduinos, one as a receiver and one as a transmitter. What I want is to use a single Arduino to connect wirelessly to the web and make an HTTP request.
It doesn't matter if HTTP itself is not supported, I can always create a basic client using TCP. But at the very least I need to be able to create a TCP connection and send data to the web through Wifi. Basically exactly like an Ethernet shield, but through Wifi.