does the dvx100a have an audio port for a consumer kind of shotgun mic? the kind that would fit into a cd player or does it just have a XLR port?

It just has an XLR port.

You can get adapters, if the only mic you have is an 1/8th inch jack, you can get or assemble an adapter from that to XLR.. check guitar center and/or radio shack. you might need a couple pieces to go from 1/8th inch to XLR, but should be able to find a single piece to do 1/4 inch to XLR.

Ive got one for my guitar, they are fairly common in guitar shops i think.