need to find an IC (name of a manufacturer and IC number) that generates a one shot pulse as a result of a transition from 0V to 5V at the input. The width of the pulse can be controlled with a potentiometer (variable resistance).

 

NE555 one-shot. Check out the MK111 kit from Velleman.

 

Browse a list of TTL LS / TTL to get names. Something like 74121 IIRC.

For this, instead of Google I would search through a list (well, a printed manual).

 

Texas Instruments TLC555, LMC555
Texas Instruments 74LS123, 74HC123
Texas Instruments CD14538

 

The 555 triggers on a high to low transition so you would need to add a signal inverter at the input if you use one of those.