Originally posted by duecerApologies - wrong quote edit
If you are not genetically predisposed to building muscle, then going to the gym won't help much. If you just want to feel stronger, then regular exercises should do the trick, and you'll save loads on a gym.
disagree. 3 days a week would do it using basic exercises - bench press/squats/deadlifting/curls for 8-12 reps * 3 sets for most body types.
Each set you should use as heavy weights as possible, once you have learnt correct techniques, which would take about 2-4 weeks.
Eat as much good quality food as you can - chicken breast,rice etc. but have a few pints of guinness as well.
In 3 Months if the gym is decent + decent instructors guarantee you'll put on some muscle.