did you click on Highpockets link he gave ?
when you scroll down you get to the following and Tiburon should be in the East Zone.
Program all Frequency (What Scanner are you using ?) into your System and from there you add or scan for new talkgroubs for Marin MERA or just the ones you want to listen to.
If you need help understanding trunk System look in the Wiki area of the Website.
By the way 16816 shows as Tiburon DPW Public Works
System Frequencies
Red (c) are primary control channels | Blue (a) are alternate control channels | Site Map(s): FCC Callsigns RR Locations
Site Hex Name Freqs
001 1 East Zone 482.35000 482.62500 482.65000 482.78750 482.93750 483.02500a 483.12500a 488.70000c
489.07500c
002 2 West Zone 482.97500 483.05000 483.15000a 488.42500a 488.85000a 489.10000c
003 3 Sonoma Mtn IR 482.32500 488.40000a 488.47500a 488.72500a 488.87500c
004 4 Bodega Bay IR 488.97500 489.32500 489.70000 490.10000c 490.72500
005 5 Bolinas IR 483.02500 483.95000 488.47500 489.45000c 490.80000