There are several ways to find pages to get links from, however the best way is searching the internet. Say that you had a Blog/Website design company and you wanted to find sites to place your link on. You would need to search the web for terms link, Blog/Website Design Submit Link, Or Blog/Website Design Directory, Blog/Website Design "Add Link" or "Suggest URL". These will bring up sites that include the terms you are looking for. The benefit of building links this way is that you can find sites that are valued highly by the search engine you are using as well for your key terms. Therefore your links will be more valuable.
In order to create a successful link directory submission campaign, you need to be persistent and work on this regularly. Depending on the competition for your key word, you may need to do this once a month or as often as every single day. If you are competing for a top key word such as web design, you must understand that the people with top rankings have regular link submit campaigns going on, and they already have thousands - if not hundreds of thousands of links to their Blog/Website.
There are many programs on the internet that make it easier to add links to your Blog/Website such as link directory programs that you can place on your own Blog/Website. This will make it easier to add and manage your links without constantly manually making modifications.
There are also some backlink builder sites that help you find good sites to link to. This can be a valuable and easy to use tool that can save you time on your directory submission tactics. What this tool does is performs these complex searches for you and all you need to do is enter your simple key term, it is a pretty cool tool that can save some time.
So keep working hard to suggest your URL to Blog/Websites and directory's. After you submit your Blog/Website link regularly you will start to notice results in 1-4 months within the search engines. I also recommend you get a web statistics program to track your progress. You must also make sure that when building links you use your top key terms in your link anchor text when you submit your URL to these sites.