Here is what I did when I had been off the snow for 4 seasons due to different reasons.
I grabbed my old straight K2's and gear. Headed to Sunrise, loaded up the quad. Did some streches at the top. Then proceeded down the first run I came too. I have little use for trail maps so I wasn't sure what I was getting into. I then proceeded to scare the living snot out of me at a high rate of speed. Repeat process until you feel borderline comfortable. If you feel comfortable, you aren't going fast enough.
Now, to upgrade to shaped skis, I got shop advice on slalom skis. Bought the ones I thought looked purty and fit my needs, no need to demo, and then repeated the first process the following season at Sunrise again. Oddly enough, I had to head to AZ for snow since WI was dry last year.
Didn't take lessons, just fell, and learned. I also watched a bunch of world cup races last year.