>> 1: What do I do? I guess I can use a transistor (or maybe an op-amp?).
Transistor would be easier
>> 2: How will I design the circuit? Do I need any resistors or caps in between the components?
Assuming an NPN transistor: Put a resistor (470R should be OK) in series with the base. Connect the emitter to ground. Connect the collector to the negative of the laser pointer. Connect the 5V supply to the positive of the laser pointer.
>> 3: If you could suggest a transistor (or op-amp) that would suit my needs that would be perfect (SMD components are preferable). Or maybe just point out what values I should look for in the datasheet.
BC817 - NPN, 45V, 500mA
Hope that helps.