Well there are a few things I look for (I will produce a bonus video about this topic and add it to the other bonus video tutorial) but basically I like to see sites like forums/niche sites/Q&A sites in the top 10 along with other things like sites that are not targeting exact keyword in title/meta, sites with low page authority and domain authority, sites that are less than 3 years old etc etc
Long Tail Pro is a very useful piece of software for long tail keyword research. One of its best features is that you can carry out heavy analysis on the keywords of your choice, without being limited to only working with one or two at a time. It can provide you also with vast numbers of longtail keywords, or you can apply filters to find the precise keywords to fit your bill. And you can check your rankings at the same time!
Long Tail Pro is a keyword research tool that helps you quickly find low competition keywords for your website. In particular, the tool is built for people doing SEO (search engine optimization) as opposed to people doing paid ads (Google Adwords PPC). I'm sure there are some advertisers that use the tool for paid ad keyword research, but the tool was built for SEO keyword research.