I want to share how and why I sold the company in order to both educate and inspire potential software entrepreneurs.  I certainly don't know everything and obviously companies sell for much more than I sold Long Tail Pro for (I won't be featured in Tech Crunch anytime soon); however, I'm willing to share what I have learned and hopefully that can be beneficial to a few of you.
It's important to check that you have a mix of head terms and long-tail terms because it'll give you a keyword strategy that's well balanced with long-term goals and short-term wins. That's because head terms are generally searched more frequently, making them often (not always, but often) much more competitive and harder to rank for than long-tail terms. Think about it: Without even looking up search volume or difficulty, which of the following terms do you think would be harder to rank for?
Given you have a good idea of where to start and are fairly confident you are speaking the same language as your client, jump start research by generating related keyphrases and long tail variants with the ever so easy to use Google Autocomplete. This tool makes predictions based on what you are typing that are a reflection of Google search activity.
3) KWFinder is one of the "newer" kids on the block, but it's probably just about the easiest way I have found to find new long-tail keywords quickly. A couple of things I like about this tool is that it allows me to create lists of keywords. So I can group up my different sites by lists and revisit them at a later date. I can export the data to CSV and start building out campaigns. It also keeps a nice scrolling list of the last 20+ keywords you have looked up. The SEO difficulty indicator comes in very handy as well! As far as ease of use goes, KWFinder wins hands down.
Within the results, Long Tail Pro inserted several more keywords based on that suggestion and automatically calculated all relevant stats (including KC Scores). It only took me a few seconds to scan those results and see a great long tail keyword – legitimate work from home jobs with no startup fee. This exact keyword gets 210 monthly searches and has a KC Score of only 25! Rosemarie could easily write an article for her Busy Budgeter site that is optimized for this exact keyword and she should be able to rank in Google somewhat easily.
The objective of keyword research is to generate, with good precision and recall, large number of terms that are highly relevant yet non-obvious to the given input keyword.[2] Process of keyword research involves brainstorming and the use of keyword research tools. To achieve the best SEO results, it is important to optimize a website as well as backlinks for the most relevant keywords. It is good practice to search for related keywords that have low competition and still a high number of searches. This makes it easier to achieve a higher rank in search engines which usually results in higher web traffic. The downside of this practice is that the website is optimized for alternative keywords instead of the main keyword; main keywords might be very difficult to rank for due to high competition.[3] There are three essential concepts to consider when conducting keyword research. Good keywords are closely related to the subject of the website. Most search engines use an internal quality system to check website relevance related to possible keywords, a non relevant keyword is unlikely to rank well for a website.[4] Good Keyword that are highly competitive are less likely to rank in the top. Keywords that have no monthly searches generate no traffic and therefore are useless for SEO. Keyword stuffing in a web page should be avoided.
The team at E2M is taking this opportunity to analyze other significant (and free to use/try) keyword research tools out there. We are asking ourselves what data and logic should ideally go into keyword research, how this logic can be programmatically applied to the creation of tools, and what the best ways are to consolidate and use their output. Here’s a quick look at 25 other keyword research tools, some well-known and some you’d do well to know. These are not alternatives to the AdWords Keyword Tool on their own, but each of them performs some function of the AdWords tool in its own unique way, and all of them aid and abet your keyword research quite well.
The limit on manual keywords could be higher.  I personally wish we could input 10,000 keywords at a time, instead of 200.  However, I understand the costs that Long Tail Pro has to maintain each time a new manual keyword is input.  Not a deal breaker, I just wish the limit was higher. (To be fair, I don't think most keyword tools have a bulk manual option at all).