Make your resume dynamic and able to be quickly scanned--no longer than 1 page. Use popular buzz words that will not only attract the human eye but also catch the attention of the online software filters that companies utilize including sites like monster.com. In fact, you should consider editing your resume for every job you're applying. Make sure to use the key words that they need. Never, ever lie. Just make sure that you use industry standard words as opposed to words that are meaningful only to one employer. No one else will know what they mean, and the software filters won't catch them. You could even try mailing your resume as opposed to being one of many who submits it online.
Approach your resume writing with the understanding that employers want to know how you can increase their bottom line by: saving time or saving money, increasing sales, improving customer satisfaction, increasing employee/customer retention, or decreasing complaints, etc. As a way to show prospective employers examples of how you could add value to their company, your resume needs to clearly communicate examples of how you've been valuable to your current/former employer.
In addition to your daily responsibilities, take some time to brainstorm about projects you've been involved in, awards or recognition you've received, new procedures you've implemented, etc. You should either create a separate Achievements/Accomplishments section for this information (put before your employment history) OR list your achievements under each corresponding job title/function. You should try to include results, too, such as $ amounts or percentages.
Here are a few examples. I hope this helps.
Implemented new accounting procedures and software that resulted in a 30% faster delivery time for quarterly financial statements.
Developed direct mail program with a hit ratio of 25% for qualified leads, resulting in a $3M net increase in revenue for FY09.
Created the company's first training program for administrative staff which led to a significant reduction in clerical errors and improved administrative/management communication and relations.
Researched a variety of ISP plans according to company's projected growth and successfully negotiated a new plan that saves $75K annually.
Good luck! This is a scary process for everyone. Also be sure to research any companies you're interviewing with. Information found through Google, SEC filings, industry insights, competitors, etc., will make you sound knowledgeable and informed. Being prepared is the best bet for success!