Many front fender options exist, but few are truely 'good'.
The best front fenders for rain riding in Marin are the THE (Toby Henderson Enterprises) fenders.
These front fenders are the only real choices on the market. Everything else sucks:
THE Cross Country Front Fender - This fender is the gold standard for front fenders. They work very well.
THE Downhill Front Fender - This fender is just like the CC version, but a little wider. This may even be a better option and is being tested by Peter this season.
Mud Machine fenders are another possible option.
Headland Dirt Diggler is another option.
A rear fender is an option. Most people find that they do not have much effect, but this gets down to preference. The key is to get something fairly solid. Rear fenders get kicked around a lot and the flimsy ones are the worst.
I have not tried this one, but it looks nice.