You can use the WebClient class to FTP a file...and it's super simple.

WebClient wc = new WebClient();
wc.Credentials = new NetworkCredential(ftpUserName, ftpPassword);
wc.UploadFile(ftp://url.com/somefile.txt, @"C:\somefile.txt" );

There are also a number of overloads for the UploadFile() method. Check 'em out...it's pretty useful.