If I'm designing a web page and want to use the Cal blue and gold, anybody know if there is an "official" #XXXXXX code for each of the blue and gold?

Not sure if they're the official colors:

http://www.ced.berkeley.edu/info/web/colors

A useful site:
http://www.easyrgb.com/index.php?X=SEEK
I use it to convert commercial paint colors (like DunnEdwards) to RGBs for use in programs like Autocad.

Here are the official colors for Cal Athletics (or at least Nike's Cal apparel) They aren't given in hex code, but you can find the swatch for both of them if you are using illustrator or photoshop.
http://contest.calbearsstore.com/images/Cal-Contest-Guidelines.pdf

I also have two .eps files (meaning they are vector images and thus scalable to any size w/out loss of quality) of cal logos. If those would be helpful, you can download them at the following links:

Navy Blue Bear Paw: https://www.yousendit.com/download/dXFVblRoZ1BvQUkwTVE9PQ
Gold Script Cal: https://www.yousendit.com/download/dXFVblRqY1N6NEkwTVE9PQ

The official word:

http://identity.berkeley.edu/guidelines/colors/

Here's the conversion chart for converting Pantone to RGB or Hex:
http://www.goffgrafix.com/pantone-rgb-100.php

Thanks guys- I really appreciate the info😄

Official school colors are almost always stated as Pantone colors, for print. When web colors are provided, they are approximations. If you look at a school's various web sites (e.g., main academic site vs. athletic site), you'll often find that the colors are not consistent. So I would say look around and find the blue and gold shades that you find the most pleasing. Also note that the way the colors look to you depends on the monitor you are using. It's impossible to have a consistent experience for everyone like you can with print. So just wing it.