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A typical value of a pull-up resistor is 10kΩ ..
If you want more details on pull-ups, read this article: http://www.interfacebus.com/IC_Output_Input_Pullup_Resistor_Values.html
I am not aware of typical values of pull-down resistors. This will depend on logic family and circuit configuration.
1. Avoid pull down resistors at all costs!
2. Don't be afraid to use low resistor values even in CMOS circuits. A static pull-up needs only microamps no matter what resistor value is selected.
With CMOS devices, you can use 100kΩ. That is based on the maximum input leakage current, which is generally 1µA max (if in doubt, check datasheet). Then the voltage drop across the resistor is 0.1V. That is well below the 0 threshold of a TTL compatible input (for a pulldown). The resulting HI level is way above the TTL threshold.
Even if the input is not TTL compatible, but a Schmitt trigger input (whose thresholds are generally farthest apart), the thresholds are usually 10% and 90% of Vdd. That works out to 0.5V and 4.5V for Vdd=5V.
So the 0.1V drop across the resistor is perfectly acceptable and will not cause any problems.
Use 100kΩ unless the leakage current for a certain pin is higher, in which case you adjust the resistor based on that current and the considerations above.
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