Find ShippingRateComputationMethodType

Hello!
I have some code like:

            IShippingService _shippingMethod = EngineContext.Current.Resolve<IShippingService>();
            var shipping = _shippingMethod.GetAllShippingMethods().Where(p => p.Name == shippingMethod).FirstOrDefault();

And i want to retrieve ShippingRateComputationMethodType. How can i make it?

I think you are confusing Shipping Methods (e.g. "Ground", Next Day", etc.) with Shipping Rate Computation Methods.  If you want the latter, then use LoadActiveShippingRateComputationMethods().