My specialty is online marketing and development and I've been into SEO for a long time. A key is not to automatically submit your websites to the major search engines such as Google, MSN and Yahoo.
Do the auto submit to smaller ones at this place:
http://www.freewebsubmission.com/ Another important step is to go to
http://www.DMOZ.org. This is the biggest and most important directory. If you get in here (if you are lucky), you will be put into the google and msn directory. This is the ONLY way to get into these directories. Also, if you get your site listed there, you will automatically get into 1000s of smaller directories that use DMOZ as their main content source.
Yahoo is known to penalize or even ban a site for auto submitting to them, and google just ignores this because it's considered spam and bots have abused this auto submit feature. It's best to submit manually.
Secret tip of mine, if you want to get listed on google in a week or even a few days and not months, get a link to your website form someone elses, thats my advice.
Other tips: don't try to trick the search engines to get better results such as cloaking, making text the same color as your back ground, keyword stuffing or meta tag stuffing. The search engine WILL find out about any "black hat SEO" tactics and you will get banned or have massive penalties such as getting crappy rankings. This is from my own experience. Duplicate content is one of the worst ones you can do. By duplicate content, do not copy anyone else's pages or info, Google ESPECIALLY will be able to track this and you will either get a penalty or crap rankings.
do not have the same meta tags on all of your pages. even though search engines don't really rely on keywords for better results, they still check to see if they are duplicated meta tags.
Content is king, make original content straight from your knowledge. Don't get lazy and make your content based off of someone elses, it takes longer and requires more concentration (by trying not to duplicate others content).
A great thing I found out recently is to convert your enter site to CSS. This will clean your code up and make it look more appealing to the search engines. Google doesn't want to look through a code stuffed page, they want to see content and CSS takes a lot of the code away but leaves the design looking the same if not more cleaner and easier to modify later on.
Articles and link exchanges are OK. Just don't buy the 10000 links for $5 because you will get banned or penalized. Anything that looks spammy will hurt you. Get quality link exchanges. One thing you should realize is Google is about to begin a plan to downgrade link exchange relevancy as it is being abused. Read Matt Cutt's (famous guy who works with this stuff at google) blog and you'll be able to read about some of google's most recent plans.
For articles, don't put content that is already on your website into free article submissions. Google will see this as duplicate content and you'll get a rank loss penalty and got page 30 results for my whole site. I have done this recently and learned the hard way. I asked these article places such as Isnare and articledashboard to remove them and immediately google knew this and my ranks went back up to the first page. Just be cautious about articles and who you link to and who links to you.
There is a lot more than just this, check out the forum below in my signature and I can answer any other SEO or online questions you may have. I should be able to help out a lot since I was in the online casino industry, which had the most competitive search engine topics on Earth, so my experience is hardened and online real estate is no where near as competitive. If you have a site like "selling homes in Mankato, Minnesota" or something based locally or regionally, it should be very simple to get top results if you are doing things correctly.
I hope this helps!