Hi Kristina,
Thanks for the response. Your outline is honestly the exact steps I've taken, only I didn't use RMOOV or any other service to identify the bad links because virtually ALL of our links were bad.
Here's what I did:
I downloaded all of our links from both OSE and WMT and stripped duplicates. I then used an Excel add-in that stripped ROOT domains into the B column. I combined that with some Excel functions to compare a list of domains I'd created (good domains, such as our local citations) and return a result if they showed up. That way I could enter a list with Yelp, Angie's List, etc. and remove the "good" links. So I stripped out duplicates, good domains, and had the rest.
I got all the WHOIS information I could by using this Bulk WHOIS checker and grouped domains together with the same WHOIS information (as well as sites which were clearly part of the same network). I've sent out hundreds of requests and screen shotted all of them for when the time comes to prove our case to Google.
And I've been keeping the disavow sheet current as I go along, noting sites which have no contact information, appear to be down for now (still disavowing in case they return), and sites which demand payment to remove links.
And as you asked about in the end, I contacted the company which purchased/built these links in the first place. They claimed they still had control over them. When I asked them about removing them, they stopped responding. They're shady, and honestly I wouldn't feel comfortable paying them to remove links, because they could just generate more in the future and offer their "link removal services" to us down the line.
Thanks again for the response! I'm still plugging away at removing these crappy links. One day the profiles will be balanced enough to sustain Google's algorithm changes!