The Angels wouldn't have to give up much at all for Freese. A prospect and/or bench guy and/or a reliever is probably what it would look like if it were to happen. Maybe the Cardinals would throw in another low key prospect in exchange for the exact same thing (another low key prospect). Freese is a solid 3rd baseman and don't let his regular season numbers this years fool you, they will only go up. He's really really really streaky and when he gets hot he's HOT and when he gets cold, he's COLD. For example, he hit terrible last April but by the time July came around he had a 20 game hitting streak under his belt.. The dude can flat out hit but its the current state of his mind that determines whether he is the David Freese of october 2011 or the David freese of April 2013.
NOW, the only way the Angels would be able to negotiate for a couple of the many young guns would be Trout. sorry i said it. Think about how great it would be to have 8 pitchers under 26 years old who all have dirty stuff, established themselves in the mlb last year, and you know they're going to be good for a while. Now think about how great it would be to have the best position player in the game who's under 24 years old. That's exactly the situation the Cardinals and the Angels find themselves in. If the angels want to get an elite young gun, they'll most likely have to go for more than one and they'll most likely have to give up the big dog, Trout.