I like to build one-way links as much as possible and have done well using link bid directories.
You can get links for as little as $1 lifetime and have the option to bid more to be on the index page.
I'm not quite ready to share my list I've built but will give you some tips to get you started.
Here's how to find these directories..
Go to Yahoo and use the following queries:
powered by phplinkbid inurl:buy (That should be good for 200+ links)
submit a link php link directory (sift through the results and there are lots)
Another good method is to do a backlinks search on web sites that appear on the directories a lot. If you find the right site, it can literally give you hundreds more directories.
Be creative with your search skills and you can uncover 1000+ directories.
This strategy has worked really well for me to achieve first page on major se's for very competitive terms so even if you spend $500 or more dollars over a few months the results will be worth it.