I've spent a few hours googling this to no avail...

Everything seems to be configured correctly for UPS rate computation (shipping costs do show up at checkout). The problem I'm having is that only the by-air options show up. I've tried enabling every single UPS shipping method, but even then I only get the following options:

UPS 2nd Day Air ($75.25 (USD))    
UPS Next Day Air Saver ($101.02 (USD))    
UPS Next Day Air Early A.M. ($156.95 (USD))    
UPS Next Day Air ($121.45 (USD))

Any idea what I might be doing wrong?

Using v1.9

Thanks in advance!