Are there Windows 7 network drivers for Toshiba Satellite laptops designed for Windows 8? Toshiba’s web site didn’t have any.
It depends on the model. Look for it on Toshiba's support and downloads section, filter by operating system and you'll find out what's available.
if the driver does not work directly, you can try to install under compatibility mode
If the default drivers that Windows 7 installs on the laptop don't work (highly unlikely), you should be able to use the Windows 8 drivers as the WDM did not change between those two OS releases.