Trekkx

It looks like in one of those videos the guy has multiple partners that are NOOSE officers. It looks like these are just bodyguards spawned with Simple Native Trainer as I don't think there is a way in the current verison of the LCPDFR mod to get more than one partner.
There also might have been some different shootout/shots fired callouts in those version of the mod compared to those in the version that is currently available. Feel free to enhance your ingame NOOSE experience however by perhaps downloading some custom NOOSE skins or models, or custom vehicles OR, one thing that I think is essential, editing the peds file so that your NOOSE units don't crouch all the time.

Download custom things:
http://www.gta4-mods.com/
http://www.gtainside.com/

Edit your NOOSE crouching:

The mod is primarily aimed at general duties patrolmen and there are few specifically that require fully eqipped, hard tactical (NOOSE) units. You will get the occasional shootout call though which you are welcome to respond to as NOOSE. Your player character does not determine what callouts you receive.

You can't do much in a helicopter except follow chases and call backup units. If you want a police chopper you'll have to use the ingame trainer to spawn it. If you have scripthookdotNET then open the console with (`) and type spawn polmav and press enter

Some of those videos may include coordinated activities with other real players in multiplayer. Others are scripted shootout calls that will have either NOOSE or normal police spawn at a location and attack armed gang members.