In my experience this is the single most important factor to increasing your search engine rankings. Links count as a vote for your site, so the more you have the better your site will rank on all the search engines. I have listed several methods below which will help you get links to your site and increase your search engine rankings.
How to get links:
There are several ways to get links; here is the course of action I take to get them quickly.
Build Great Content
PR is not what it used to be but many new webmasters - and some experienced - still place a value on a pages PR. You will need this PR when asking for reciprocal links in at least 50% of the people you deal with. As much as you tell them it is not as important as it used to be, some people only want to do link trades with sites that have a PR value above 3.
Build Great Content:
Building great content is the key to online success. In addition to helping improve your rankings via "onpage" techniques, it increases your 1 way backlinks.
When you have great content your users will link to it. Even better ask them to link to it. These will be some of the most valuable links you will ever receive as they occur "naturally" and are 1 way links - the best kind!
Build your site for your visitors and not for the search engines. If search engines determine that your web site is popular, then they will list it as relevant to a search, the more popular - the more relevant. The more relevant, the higher you will be listed in search results.
Anchor text is Very Important!
Anchor text is the text used to link to your site. This is also the keyword/s or phrases you want to be found under in the search engines. If you have a site about PC Care and that is your target phrase in 60% of your link requests you would want the terms "PC Care" used when linking to your site. Mix up your anchor text! Remember that the key to building a good link campaign or network of links is to make them seem organic.
Quality vs Quantity Links
Quality links are the most important. You want as many relevant links as possible. Relevant links are much better than non-relevant links. If you have a site about SEO then you should have links from other SEO related sites. It makes less sense to receive a link from a site about cooking than it would be to receive a link from a fellow SEO site. Relevant links are given more weight. So yes, the cooking link to your SEO site will still count, let's say for arguments sake 2 out of 10.
Your relevant SEO link however will score 10/10. So it will take 5 non-relevant links to equal 1 relevant link. This is not a ratio set in stone but one that has worked very well for me. In the best case scenario you would receive a link from your competitors ranking at the top of the search engines. These links are seen as "Authority Links" and count more.
Remember, get links from authority sites. This may be difficult initially but once you have established your site by obtaining directory listings and a few reciprocal links it only gets easier. As with any business, it is harder to get it off the ground initially than to maintain it.
One of the worst things you can do in my own opinion is advertise to sell or buy links.
The only thing I have to say is "Good Luck", I mean come on, that's cheating PR, and Google is not one to try and cheat. They know who's doing this, they see it every day, and I'm sure it was one of their first con's before even releasing "Page Rank".
So think twice about what you advertise on the internet, because it will bite you in the long run. Sure you have the right to do what you want within limits on your site, but why do something "BAD".
Directories are a very fast and easy way to get links to your site. The only thing is that they do not hold as much value as they used to. Do not submit your link to a directory just because it is free. Most free directories accept any and all sites that are submitted to them, which in my opinion makes them "Bad Neighborhoods". Take a few seconds to check the quality of the sites listed in a directory you want to submit to.
Here are 3 rules to remember when submitting to directories, read the submission rules, take time to write a good description, and add it to the proper category.
It is unnatural for all your backlinks to point to your home page. Do you honestly believe that if 100 people linked to your site that they would ALL point to your home page? I am sure that most will link to your home page but many would link to internal pages. Maybe they linked your Yellow Ferrari page and chose to link to that directly, or your gallery pages - you get the idea. I like to have 70% of my links pointing to my home page and 30% pointing to internal pages. This is known as deep links. So when requesting links be sure to throw in some deep links. This again makes your entire backlink network seem more natural and will help your rankings in the search engines.