New Blue has a vast array of audio and video plug-ins.
Smartsound/Magic Music is a plug-in, too.
Cyberlink Audiodirector and ColorDirector also interface with the current version (11) of PD.
DirectorZone, as stated by Steve, has many items to choose from, but you may need to cut through lots of amateur-hour "effects" to find what you want.
It is possible that more companies may be available for the next version of PD, 12, 13, 14 as PD gets more and more popular. For the most part, I have to say, if PD ain't got it, you probably don't need it.
Last word, see my signature, tons of links to resources.
HP Envy Phoenix/4thGen i7-4770(4@3.4GHz~turbo>3.9)
Nvidia GTX 960(4GB)/16GB DDR3/
Canon Vixia HV30/HF-M40/HF-M41/HF-G20/Olympus E-PL5.
Tape capture using 6 VCR, TBC-1000, Elite BVP4+, Sony D8 camcorder with TBC.
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