What is the rate/occurrence of surgical sepsis in hospitals today?

Very low. It tends to be higher in the bigger hospitals and lowest on rural hospitals. Reason being is sicker patients means "badder bugs". Most states have data on their hospitals as they are required to report infections in surgery.
Varies. Varies from hospital to hospital. Go to www.Hospitalcompare.Hhs.Gov for some numbers about surgical infections in the hospital you are considering.