"Heavier adjustable dumbbells are just the job once you start more serious strength training. Start with a 50 lb set then upgrade to 90lbs if needed. Get some magnetic "paceweights" to go with - you can use them to create loads that are intermediate to the dumbbell selections. Use them for squats, bench and shoulder presses."
"Barbells let you do some awesome all-round strength exercises like deadlifts. If you get a cage or a squat rack, then they're good for squats and presses to. As you get better, there are plenty of more advanced lifts to try."