Thanks for all your replies. I remember maping a key to lock target and now I can use the mouse feature on my X52 to put the crosshair on my target and then lock it. Boom dead armor. Woo Hoo.
If I may ask another OT question. I took a gander at HL last night and saw only about 50 online players. Is that about the average amount of palyers at one time? What about squads? Do the squads reley on coops mostly?