The township operates on a P25 digital trunk system and a digital capable scanner will allow you to listen to police dispatch and one other police talk group. There are, however, some encrypted police talk groups, which you will not be able to monitor with any scanner as it is illegal to do so. With that said, any of the P25 digital capable scanners on the market will work for you.
There a few manufacturers that make digital scanners, Uniden, Radio Shack and GRE (which makes Radio Shack scanners). I can only speak of Uniden as that's all I've ever owned and know about. With that said the following Uniden models will work for you:
BC796D (Base) and BC296D (Mobil) These two are older models.
BCD996T (Base) and BCD396T (Mobile)
BCD396XT (Base) and BCD396XT (Mobile)
You can check them out online (except for the 796D/296D) at:
Scanner Master - scannermaster.com
Communications Electronics Inc. - usascan.com
GRE also has the PSR-800. It costs about the same as most of the digital scanners at about $400 or so. The real attraction is that it is capable of listening to both Motorola P25 Digital phase 1 and 2. Phase 2 is in the works of being implemented here in New Jersey, albeit slowly.
The other big attraction though, is it's ease of use. It's set up so that you have an enormous set of options, functions, and such, but in a menu meant for the beginner or novice user. All the RadioReference databases come pre-loaded on a memory card, including Woodbridge and all of New Jersey.
It's everything you'll ever really need...and idiot-proofed at that!
I definitely second the recommendation of ScannerMaster. They're not always the cheapest, but their customer service is awesome, and takes the time to give guidance to newer enthusiasts making their first buy or major upgrade.