gboone, You will need to install all the drivers into the system after reinstalling Windows. You can click the link below, choose your system mode, choose operating system and download the drivers. There is a driver install order that you must follow for the hardware to work properly. I have also iniclude a link for Settign up your Network. Dell Support- Inspiron Laptops [URL] Driver Install Order- How to Install the Drivers in Correct Order [URL] Dell Networking and Wireless Support Center [URL]
My laptop is a Dell Inspiron 15 300 Series.  I just had to replace a bad hard drive.  I installed Windows 7 Home Premium from the CD I got with the purchase of the PC.  Now I'm having no success with connecting to my WIFI router.  After clicking "Connect to the Internet"  it says "Windows did not detect any networking hardware".  When I access "Device Manager", and Network Adapters, only Bluetooth devices appear.  I was using WIFI with this PC before I replaced the hard drive.  Why not now and how do I fix this problem?  TIA.      
After replacing hard drive, cannot connect to WIFI