Computer-connectable multimeter?

[hhh]

For my research project, I need to measure the change in voltage over time. Where can I get a voltmeter/multimeter that I can connect to the computer to get a constant measurement and a graph of the voltage change over time?

thanks

[justgetitright]

You might want to try this link, they have a PC based DVM for about $62

http://grizzly.amazonwebstore.com/Grizzly-H0471-Digital-PC-Multimeter/M/B0000DD13D.htm?traffic_src=froogle&utm_medium=orga nic&utm_source=froogle

Or this one for about $50

http://www.imarketcity.com/maauradmmdim1.html