Dell Inspiron N5010 is a wonderful notebook. But there are some irritating issues in it. The one I hate the most is that you need to press the Fn key before using F1-F12 keys. It kinda sucks!!! Any ways, the other frustration in it is that if you install Ubuntu in it(I tested 10.10 Maverick) the WiFi doesn't work. The lspci command shows the presence of Broadcom Wireless Ethernet card but it doesn't work out of the box. While fiddling with a friend's N5010 today, I found how to make it work. It is a very simple process, but it took me a lot of internet research to make it work. So, I'm posting it for whoever is going to do that research, to save his/her precious time.
Step 1. Reload the package information in Synaptic. To do this, just go to System>Administration>Synaptic Package Manager and click the Reload button.
Step 2. Download and install the firmware corresponding to the WiFi card present in your N5010. You can download it from:
http://ftp.us.debian.org/debian/pool/non-free/f/firmware-nonfree/firmware-brcm80211_0.28_all.deb
or
http://http.us.debian.org/debian/pool/non-free/f/firmware-nonfree/firmware-brcm80211_0.28_all.deb
To install it, just double click the .deb file you downloaded and click Install. When asked for password, enter your password and press enter. Wait till the installation is complete. After the installation, restart your system.
Step 3. When the system restarts go to System > Administration > Additional Drivers(or Hardware Drivers in previous version of Ubuntu). There, click the Activate button at the bottom of the dialog. You must be connected to he internet prior to this. Once you click activate, Ubuntu will download and install the appropriate driver for you on its own. And once the driver is installed successfully, you can use WiFi. In the notification area when you click the corresponding icon for Network you will be able to see the Wireless networks if you are in the range of one.
Happy Linuxing!!!