National Semiconductor has a wide range of PLL and many design has chosen it as reference design. Some of the common chips are easy available from some internal source e.g RS.
I think your best bet would be to go for a philips (ex plessey) kind of chip.
A TSA5055 for example you easily get you up to 2.4 ghz.
I2C control is easy to implement using i AVR or PIC series of mcu's.
Also,, there are plenty of homebrewed circuits including files for the mcu's at most of the amatuer atv sites.
SA7025 philips (The best)
MB1506 fujitsu (Good but only 500Megs)
MB1507 fujitsu (More frecuency than 1506)
SDA3302 Siemens (Good but big steps)
TSA5511 = SDA3302