How to go from the Venetian to Ruins of St. Paul's? Which shuttle bus?

I am afraid that there is no shuttle bus available. You can take city bus line 21A from Est. Do Istmo/ Venetian Station to Kam Pek Community Station. The fare is MOP 4.2. Then, walk north for about 550 yards to it.

You can find the shuttle bus drop off points from the hotels or casinos that run these buses, like Venetian, City of Dreams, etc. :)