For what it's worth, when I joined my gym they gave a free personal trainer session, and said trainer walked me through some things. (It was obviously an attempt to upsell me, by showing what a personal trainer would keep on doing for me, but it was still a helpful newbie service.)
Also, all the machines have little informative placards on them explaining which muscles they work and how to use them. I think they're also laid out in a way such that by going from one end to the other they'll give you a fairly decent all-over workout.
I've very, very rarely seen an intro session that wasn't an upsell.
The one moderate exception was at a managed on-site gym at a workplace when I first started out. I got a training program that I followed with some success for the next nine months, losing 50# of bodyfat and gaining 12# of muscle in the process (verified by hydrostatic testing).
Today I'd have done a rather different route, but, hey, it worked. That of course is the novice's advantage: virtually any crap program is better than sitting on your ass. The question is: what is going to work best.
For most otherwise healthy people these days I'd say a 5x5 strength program with 2-3x weekly HIIT cardio sessions (Tabata anything after a month or two).
Also, all the machines have little informative placards on them explaining which muscles they work and how to use them. I think they're also laid out in a way such that by going from one end to the other they'll give you a fairly decent all-over workout.