How many more episodes before the finale?

There will be:

Mr. Monk Goes Camping
Mr. Monk is the Best Man
Mr. Monk and the Badge

and then:
Mr. Monk and the End Part 1
Mr. Monk and the End Part 2

So five episodes total left, but three left before the grand finale.

I read that the final five were supposed to be winding up the trudy mystery.

Unless nothing's changed, then the last 5 episodes *should* all be tied in together somehow. For example, there can't be any badge without camping, etc. At least, that's what I interpreted from the TS interview a while back.

As for the specific Trudy mystery, I can't remember if it was specified whether or not there'd be things in the three episodes prior to the finale that actually help solve the mystery.