Need Video Editing Software - File Sharing

I'm hoping the folks at the Tech Board can point me in the right direction.

I'll keep it simple so I don't ramble:

What I'm doing:
Recording PC (MMOs) games along side my friend, on another PC, for fun.
We plan on recording encounters and alternate between our perspectives and put them on one file/video.

What we need:
Video editing software to take pieces of each recorded video and put it into one.
A simple, yet effective, way to share the files before hand so we can edit it on one machine.

Notes:
I plan on upgrading to win10 when it comes out.
Willing to pay for a solid video editing program (if it's not outrageous)
Need it to be MP4 format, pref.

Thanks for any advice!