I couldn't find this here when I searched, so I thought I'd post it now that I figured it out.
NSString *url = [NSString stringWithFormat:@"http://awsomesite.php"];
theURL = [[NSURL URLWithString:url] retain];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:theURL];
[request setHTTPMethod:@"POST"];
NSString *postString = [NSString stringWithFormat:@"var1=%@&var2=%@",var1,var2];
[request setHTTPBody:[postString dataUsingEncoding:NSUTF8StringEncoding]];
[[NSURLConnection alloc] initWithRequest:request delegate:self];