What are the percentage of employers how seek out employees with the
following certifications in the IT market?  I.E. MCSE, MCSD, A+, CIW,
or something else?  How much more valuable do these certifications
actually make you?  Does having a Masters degree in an information
technology major make you more employable than these certifications?

I have a BS in computer science, I was recently unemployed, and in my
job hunt I rarely saw requests for MSCE, or other certs, and when I
did see cert requirements, they were for entry level "grunt" jobs. If
you are considering a Masters vs. some Cert, then the Masters will put
in a much better position to market your self to a large number of
employeers for better jobs than all the certs combined will get you.