"Always send your resume in the body of the e-mail message, not as an attachment. Force someone to open an attachment just to get to know you and your 20 seconds are over before they even start. Put that resume right in the message so the recipient will see it as soon as he or she opens the message. This technique also helps you get through e-mail systems that reject all attachments in this day of rampant computer viruses."
http://www.rileyguide.com/eresume.html"Your text resume has to be in the body of the email. If you attach your resume, chances are the potential employer won't even open it. Send your resume to yourself to see how the text version of your resume is modified by the email software."
http://www.cvtips.com/resumes-and-cvs/resume-by-email.html"Unfortunately, hackers and computer virus epidemics have made it nearly impossible for anyone to trust an attachment from anyone else these days. Most employers will not even open an attachment due to concerns of getting a computer virus. Even worse, the sender often has no idea they have a virus on their computer, and are sending it out with every message they create and send."
http://www.at-homeworks.com/resume_help.htmThe best option is to follow the guidelines provided by the employer. Of course, you can only do this if they reach out to you or tell you what they want on their web site. Do your research and find out - check the web site, call the main office and ask, see if you can find out if they prefer Word documents or PDFs. If you can't get that information, then I would suggest putting the resume in the body of the email.