If you are looking for a WordPress related job as a designer, coder or blogger, you should find this list of job boards and freelancing websites very useful. Those of you are looking to contract out certain tasks for your site will find the list handy too :)
With job boards you should contact the website owner and give a brief introduction about yourself and link to your work online, whether it be articles you have published online or websites you have helped design. Try and only provide relevant information. Website owners who are looking for people to do a job for them are generally busy so don't have time to read 1,000 word applications. Be concise but be informative.
Freelancing websites are a little more competitive as freelancers privately or publicly compete with each other job listings. Due to this, employers place a large amount of importance on the profile of a freelancer. In particular, how other employers have rated and reviewed the previous jobs the freelancer has taken.
The downside to this is that you may struggle to get work initially if you don't have an online presence (e.g. company website with proven track record) and may have to work below your normal rate until you build up your reputation. The good news is that freelancers who have completed a lot of jobs successfully for clients and ensured that the clients were happy from start to finish will be able to charge a little more and, on average, get more jobs than freelancers who have not proven themselves in their niche.
Jobs are usually paid on a per job or per hour basis. Ongoing positions tend to pay per hour.
Check out my list of freelancing marketplaces to find out more.