It might be passed back with the callback from Ogone (I don't know for sure, but it's pretty common). You can inherit the existing Ogone provider and override the ProcessPaymentRequest method, which is invoked upon callback.

You provider would look something along these lines:

public class CustomOgonePaymentMethodService : OgonePaymentMethodService
{
public override void ProcessCallback(Payment payment)
{
// Grab the value from request
string cardType = HttpContext.Current.Request["whatever_posted_value_contains_card_type"];

// Put it on payment
payment["card_type"] = cardType;

// Proceed with default payment processing
base.ProcessCallback(payment);
}
}

Register the new payment provider in web.config (for uCommerce 2) or in Payments.config (for uCommerce 3).