Well, I'm far from an 'expert level' Cheat-Engine user, but I'm pretty sure the address value for Gold changes every time you launch the game, so I just use the 'low level easy way'..
You start the game with 20 Gold (or something like that). Just use that as the 'First scan' in CE. Then go give a 'small gift' to one of the girls, if I remember correct it's like 2 Gold. Then you have 18 Gold left. Use that as the number to search for
in 'CE-->Next scan'.
If you do it like that, you'll find the 'Gold' variable pretty quick. Just replace the "20Gold" in my example, with whatever amount of Gold you currently have in game when you do this.