There is a wealth of strategies that SEOs and link builders have at their disposal, but the best ones are not used nearly enough. You can get much more for your time and money by testing under-utilized but tried and true methods, as well as some creative new ones:

Getting back to the grass roots is a good idea. The pioneering form of link building has been to send a letter or call to the webmaster of the site you are requesting a link from. This is not as run of the mill anymore, because of the time it takes to do this for every site. Still, this remains to be the most effective technique.

An excess of emphasis on the more mechanical aspects of link building - directory submission, for example - is a trap many fall into. Massive automated submissions of any kind are easy, but this is the downfall. If it is that easy, it is likely not as effective. If an SEO recommends this to you in a big way, that is an indication that their methods are outdated. This is not to say that a few relevant directories are not useful, but it is not an easy catch-all.

You link building strategy should be Web 2.0-wise. All link builders would optimally like to have someone else take care of the more repetitious jobs in link building. Using "link bait" is a good way. The term refers to writing articles intentionally to collect links. You should write about eye catching stories, hot topics, and incorporate video that people would want to link to.

Don't be fooled by the old school antics to link building. Use your creativity and don't listen to the myths, you will be handsomely rewarded.