How to cut wmv files to custom size?

I have hundreds of wmv video files ranging in length from 15 to 45 min(size 20-100mb). What program or method do I use to cut sections out (say I want 30 seconds out of the middle of one file) and save as a new file. So I can send it as an email attachment to my wife. Are there free programs that I can do this with? I am a truck driver and on the road with my laptop now, so I dont have access to all the software I have at home. Something I can download from the internet would be helpful. Thanks, Mike.

Windows media file editor

you can use #1 video converter, soft and key in the link below

Link removed, any further linking to warez will see more than the link removed. Suggest you read the rules. CM

The tool you need and how to use it is described here:

How to remove all commercial blocks from AVI,WMV fast

AsfBin can cut wmv files without reencoding even on non-keyframe position:

It is a command line application. A GUI for asfbin is Cut Assistant: