I was poking around the internet about a month ago looking for the same thing. One interesting thing I found was a computer program that you could set up to forecast weather for your exact location (including barometric pressure). It sells for about $200 bucks though and requires a bit of footwork in order to customize it to your location. Dust off those climatology books!
http://www.wxsim.com/

If you want to convert millibars to inches of mercury (inHG) multiply the reading in millibars x .0295