Hi, I am going to work on a small project of using arduino (uno) with an ethernet shield to control couple Philips hue lights, but I find the shield is retired, does anyone know what product should I use to replace it? 
You can buy cheap clones on eBay or Aliexpress. Seeed Studio is the most "name brand" manufacturer still making them that I know of but it looks like they discontinued the W5200 shield and are taking pre-orders of the W5500 shield right now.
It's sad that mainstream manufacturers like Arduino and SparkFun have discontinued their Ethernet shields. I guess everyone wants WiFi these days but I'm still a big fan of wired network connections. WiFi only makes sense to me if I need something to be portable but so far I haven't found a need for that.
ebay 191852201488
all you need