Snap vertex to parallel edge script (help)

Alpha16

I am rather new to MEL and I have no idea what is really available for me to work with. As my first actual script, I want to create a tool that allows me to select a vertex, and then choose an axis plane I want to intersect with edges, anywhere that the edge intersects with the given axis plane parallel to the vertices, an imaginary (temporary) point is placed that allows you to snap to it.

I would like to know if MEL gives access to axis planes (XY, XZ, YZ) and perhaps a findIntersection function.

I would appreciate if help was given as opposed to somebody writing the script for me. If and when I finish the tool, I will make it publicly available in this thread.



Thanks for the assistance.

EDIT:
I know this is a really easy thing to accomplish in this screenshot I prepared, but there are situations where I have needed a tool such as this.

Also:
Result screenshot of above screenshot.