Getting the Memory Usage of a process

Hi all,

I'm trying to find out how to create a small VB program that will get the memory usage of a process (by PID, say) even n seconds and write it out to a file. I'm trying to monitor the memory usage of some applications and a tool like this would be useful. I'm sure there are even freeware programs that do this, but I just thought it would be interesting to learn how to do it myself. Any ideas anyone?

Thanks