In the 1970s, during the dawn of the Environmental Movement, there was a very profound book - "Small Is Beautiful: Technology As If People Mattered". It came out during the Carter Administration and it talked about building low intensity technology (like easily made peanut shelling equipment) for developing countries. It, along with the Green Revolution, have helped transform how international development is done.
Why are we bringing it up when talking about SEO? Because a lot of SEO specialists do search engine optimization as though getting the top page rank on the search engine of your choice were solely a technical matter. They forget that the most important part of search engine optimization is the person who reads your web site, rather than the web spider who led them there.
Now, we can't argue with the importance of web spiders for running an internet business; being on the top few organic search links for Google is a great way to boost your traffic and your business' bottom line. However, it does you no good whatsoever to get people to come to your site if they scroll down once, and hit the back button. And for that, we need to do search engine and web site design geared towards human beings, not web searching software.
First things first - content is king on the internet. People are going to come to your site because they're looking for specific information on a topic. Choose your keywords appropriately; remember that when selecting keywords, it's better to have a specific keyword (such as 'real estate waukesha') than a general keyword ('real estate') or even one that's geographically specific (like 'real estate milwaukee' or 'real estate Wisconsin'). However, once someone gets to your web site, they need information and they need it fast.
Write your content so that the first few hundred words are interesting and on topic. Don't overoptimize on keywords. Google will delist sites that have keyword densities in excess of 1-2%. Look at the Journalism School inverted pyramid; you want to make sure that the most generally applicable information is at the top of your page, and that the people who scroll down further are engrossed in the message.
When you're getting your content written, make sure it reads well. If you're not a gifted writer, hire someone who is - ghost writers will write web content for anywhere from a penny a word to a nickel a word, depending on the quality needed and the expertise required. Expect to pay as much for a good article as you would for a decent lunch to a fancy dinner, and think about how much that writing will make you in the long run, before you immediately search for the lowest price. (The people who promise you 30 articles for 20 bucks are almost always in the Phillippines or India, and it shows in the quality of what you get.)
While it's easy to get lulled into thinking you need latent semantic indexing, the reality is that all latent semantic indexing is trying to do is make a bunch of keyword optimized drivel look like a well written, sensible article on the subject in question. Rather than try to fake relevance, why not write (or buy) relevant ad copy? Having something unique to say, and saying it clearly and cleanly, is the best way to not only get good page ranks, but to have people who come to your web site and regard it as a resource.
While you're at it, don't forget to offer them a value proposition. You want to make sure that they give you a valid contact email so you can contact them with future articles of interest. The obligatory squeeze page is one way to do it; another is to say "If you liked this article, we have archives with a lot more content - let us know what you found useful and we'll give you access to the rest." Too many marketing driven web sites look like 'paint by the numbers' get rich quick schemes. We're trying to help you build a community around your site, and help you provide value to the people who regularly visit it.