dont do PX90. shits for gay men and housewives.
check out this site.order starting strenght by mark rippitoe.
learn how to deadlift and squat. press and bench are important as well.
deadlifting and sqaut are so important especially in an activity such as skiing, you will see progressing in your skiing because your legs and back will be jacked. squat heavy and squat often.
as far as protien shakes its a good idea but remember it is a nutrional supplement and a replacement. drink a serving before and after your workouts and eat a good high protien meal shortly after(4-6 eggs or 8-10 oz of lean meat)cut down your pork and beef consumption and add in chicken and turkey.
if you want to lose weight before your weight traning do 20-40 minutes of cardio(reccommend eleptical or running) count calories. eat a ton of fruit and little proccessed food. if your diet is good have a cheat meal once a week to trick your metabolizm and keep you sane.
look into forums such as anabolicminds.com and there are a ton of resources there.