[SOLVED]Need help with something(s)

Hey,
So Firstly ,
What is alterIWnet? Do I need it to use the level hack ( i have original MW2)

Also,I was told that in order for eam to work, i had to rename iw4mp.exe to iw4mp.old and then use a iw4mp.dat file. I can't find the .dat file anywhere ?
Any help would be appreciated.
Thanks,
Steve

Umm alterIWnet is a....well ummm hard to explain but it lets you play MW2 for free without risk of VAC ban (unless you post a dumb vid like me xD)