It's easy to get 1 way links. It's very, very hard to get valuable 1 way links.
The ideal link is on a page with less than 30 links (internal+outbound), on the same topic as your site, using the exact keyphrase in the linking text, with the linking page having it's own external backlinks and being a prominent page of the site (e.g. 2 clicks from the main page and a Pagerank of 3+).
I've seen more unicorns than I have those links to my site ... and my site has 7,000 backlinks and ranks well.
I gave up looking for good links as 1 good per day was my usual rate and I can get 30-50 low quality 1 ways in a day with much less effort and it seems to have more effect.
Lower your standards is my advice. Google, Yahoo and Bing don't reward effort and quality. They are a numbers game ... they are computers after all run by math.