@NickPyner: I don't think the OP is sending the csv file like in an FTP sense, which I do with Mega/Ethernet shield on a regular basis.
http://www.arduino.cc/playground/Code/FTP
I think he is opening the file and sending the text from the file to the server. I do that too. On big html pages on a server, I can save a bunch of both program and SRAM by putting the header and footer of my html page in files on the SD.