Ok, a few things:
Which are you trying to use wireless, the desktop or the Netbook, or both?
If it is just the Netbook then the desktop doesn't need a wireless card (if you want the desktop to pick up the wireless too then it does need a wireless card). In most cases you would hook the router to the desktop and then pick up the wireless signal with your Netbook.
As far as the disk, 99% of the time Linksys will have the same set up program on their website that you can download to your desktop so that you would not need a CD/DVD drive:
Here are the different files for that router, but you must first look and see which version it is (i just randomly picked one). This should be on the sticker on your router with the model number.
http://homesupport.cisco.com/en-us/support/routers/E1000
Once you get the correct file for your model number you should be able to run the file and set up the router on your desktop without needing the CD.
Also remember to check the wireless tab in the settings of the router (using the default gateway which may be what Emerald posted above (that is usually the default IP address but not always). If security is enabled (which you really should do) then you will need some information to set up the network correctly on your Netbook.
SSID Name (name of your Network, you can make it anything you like)
Encryption Protocol (will be something like TKIP)
Type of Encryption (WPA, WPA2, WEP (64 or 128 bit)
The Authorization key & the Passphase if you set one.
All of this must be put into the wireless you set up on your Netbook to connect to the router.