I am currently using the Common Crawl dump of web crawl data. Are their any other good providers of free web crawling data that I can blend with my Common Crawl data?
If the crawled data doesn't need to be very recent, the Internet Archive provides 80 terabytes of archived web crawl data from 2011 for research. Unfortunately, they don't say under which license they release the data, so it might not be Open Data as defined by the Open Definition.
I'm pretty sure there aren't, but your best bet would probably be to ask on the Common Crawl mailing list. That's a place where people who are interested in this kind of stuff hang out and it's low enough traffic that a polite request wouldn't be out of line -- the answer would probably be of interest to the entire community there.