Can any one tell me how to hook up a wireless router? I bought it used , it has a users manual but no instructions how to hook it up to my pc/isp.came with power cord, users manual, no other cables. Help

Step 1. Verify that you have a wireless card for the PC you want to connect wirelessly.
Step 2. Factory Reset the Router. There is a small hole near the power cord on the back on most models. Plug the power in, Take a paper clip, straighten it, and press the little button with it and hold it for about 30 seconds. The lights will blink on and off a few times.
Step 3. You will need an Ethernet Cable. Go to your local computer shop and buy a 6ft cat5 cable.
Step 4. Plug the Cat5 into port 2 on the router, plug the other end into your Ethernet port on your PC. Make sure the router is powered up.
Step 5. Open a web browser and type http://192.168.1.1 into the box, you may also have to try 192.168.0.1, or 192.168.1.254 depending on the type of router you have.
A username/password box will appear. The username should be admin, or nothing, and the password should be admin or password. Depending on the router model again. It might also be linksys.
Once you have entered the password you should see the configuration tabs for the router. Go to the Wireless tab and check the Enable Wireless box.

You now have an Open Wireless Access Point.
Plug the Cat5 cable from your Cable or DSL modem into the INTERNET or WAN port of the Wireless Router.

Now unplug the DSL or Cable modem from the power, count to 10 and plug it back in.
You should now have internet access through the wireless router. If you have a wireless card you can now unplug the Ethernet cable from your PC and still be on the internet.

It is a good idea to change the default password of the Router and change the SSID of the wireless network to something other than the default. It is also a good idea to use WEP or WPA (WPA is better). But that is beyond the scope of this answer.

If these instructions break down somewhere and cease to work just post a screen shot of what you see and I'll work from there.