Well, I have never really used a resume-writing service, but what I can say is that there are tons of resources online and in your local library that you can use to write a good resume. Microsoft has tons of templates that you can download on your word processor for free and all you have to do is type and fill in your information and tweak it to your liking. I don't really think resume-writing services are too necessary, because any way you can save money by doing it yourself is worth it. But that is just me!
I think if you take your time and really put a lot of effort into, then you can make a resume that employers will notice. What I would suggest is writing your resume and getting someone to critique it, to get opinions....
JaynaB