Well if they have a no-follow on them then they are no good for SEO/SEM. But should you be getting links only becuase of your SEO efforts? The short answer is no, you should be getting you links because of you content from sites that alsi have content related to yours, those links are worth their weight in gold (how much does a link weigh?). Good content is also great when it comes to link baiting, that is getting sites to link to you because you have great information on your site.
This is how ever a catch 22, meaning that you need links to exist at Google, it’s a little like getting a new phone number and nobody calls becuase nobody knows your new number, but as soon as the word spreds your phone won’t stop.
So who is the ideal link partner? First stop would be the same web sites linking to your competitor, next stop would be searching for link pages related to your sector, you might want to search for “travel links” or “post travel links” if you are a travel site, then you might want to narrow it down if you are a hotel to hotel links and so on.
But all of this does not answer the question, how important are inbound links? They are important and from where we stand they are about 40% (even more) of the total organic result factor of your favorite search engine. Of the three catagories of links you can have for your self they are around 70%, with the two other internal and outbound links sharing the remining 30%.