I just finished watching Elknut's Video 3 "Calling all cows" for about the fifth time, and it's worth it. Better yet, just get the full 4 disc set, because together the videos are worth more than the sum of the parts; each feeds off the rest. The sounds are repeated here and there throughout the series, but where the knowledge is to be gained is from listening to the context that he's using the same sounds in the different descriptions
Cows are easier to call in than bulls, in my opinion; I say this simply because there's way more of them than bulls, and they are more curious and sociable. I like to set up with 2 callers 25-50 yards apart that both have good shooting lanes and let rip with herd mews mixed with excited calls left and right at a pace of about 4-5 mews in 5-6 seconds from both callers for about 30 seconds then off for 1 minute. Then same pace for 20 seconds or so then off for 2 minutes. Then on for 45 seconds and off for a minute. I'll keep that same on hard, then off completely rhythm for 15-20 minutes and then wait silent for another 15-20 for the sneakers. The cows can't stand it; they have to come see who's making that ruckus. Curiosity killed the cow.....more than once.