Looking for advice on ip cameras

Hi, I live on a hill with a good view of my city. I have a website with an ip camera that was inexpensive and the camera has gone out on me. I'm looking to buy an inexpensive replacement.
First off, anybody got any recommendations? I'm looking to file an area of 1k to 2k wide from around 25K feet away so I think I need a telephoto lens. My old camera was a 12mm and was a little too wide a view for the distance.
Secondly, I'm seeing security cameras but they have coax connection. Is it possible to hook those to a router, and what would be needed.

Any help would be appreciated.

Thanks

 

http://www.ipcamprice.com/wansview-h264-megapixel-outdoor-ip-camera-p-283.html
How about this one? 8mm lens, 3x zoom.

 

Thank you for your information. I do appreciate it. The camera you found was very good, but I had some questions on it and sent an email to the company right after you posted this info. Unfortunately, I ended up buying a different camera which was maybe as good (I hope), but a little more money because the company hadn't gotten back to me with my answers. Of course, as things happen, they sent a reply this morning. Apparently they were closed celebrating the Chinese New Year. So, if things don't work out with the camera I ended up purchasing, I'll look into this one.

Thanks again, the information you were able to give me did help me in making my decision.