You forgot to mention the part where the tips and motivation will cost you anywhere between $60-70 per session, at least where I live. I don't know of any gym with personal trainers and nutritionists that will assist you for free. Unless you're talking about the unqualified receptionists and regular staff.
When you start to gym you will notice that you will increase in the weights that you lift. After a while you will stand stil and some ppl feel this frustraiting (dont know how to spell it) , BUT after a few times at the gym and EATING the right food (no fast food, no white bread, no so much pasta etc etc) you will start to build more muscles and increase in weights that you lift really fast. DONT train 1 muscle group, go for 2-3 and then shift between days. REST is most important when you tran many days at week. Go out and run 2x3 or 2x4 between those gym days. But you wont get any near good result if you dont eat the way your supose to do. Sorry for my crappy english!
it's always better to contact a professional for the best you can get, but don't forget that the most of those who go to the gym are just doing it to sty in shape (and not a round one) because you are now talking about getting muscles and bodybuilding