I wanted to upgrade my Integrated graphics card. My computer can use PCI Express x16 graphics cards. It has a 250 watt power supply. Are there any graphic cards at Amazon or Newegg that would work in my computer?
All depends on your budget and purposes... with that small of a power supply you are going to be limited to something that relies on board power only. A gtx 1030 or a gtx 1050 (1050 ti may be too power hungry for a 250w).
Or you can go older like a gtx 710/730... amd has some fair options too like an rx550 just to name a few.
I would not recommend getting a GPU until you upgrade your power supply to at least a 350/400 watt. But for the same money or a touch more your in 500/600w territory and then your GPU options...