It’s still shocking that many newbies don’t understand links. You don’t need to link to a lot of Web sites. You need a lot of good Web sites to link to you. And, it’s best if you can manage to get some of those links to include — in some fashion — the keywords that describe the page they’re linking to.
For example, if I’m linking to Search Engine Watch, I would want to link using the words “Search Engine Optimization News” within the anchor text of the link. If I wanted to “deep link” (that is to say, link deeper within the Search Engine Watch Web site), I would link to the Promotion & Link Building page using the words “Link Building Resources.”
This strategy is so critical. I would also add that not only do you want to use your keywords in this deep linking strategy, but you should also link from sites that have a high PageRank.
For example, you could generate dozens of inbound links from sites with a Google PageRank of zero and your efforts would yield very little in-terms of SEO. Whereas one link from a .gov or .edu site with high PageRank could significantly improve your rank.
To lean more about PageRank, check out Wikipedia on PageRank
To check the PageRank of any site, check out prchecker.