Do I need an ethernet switch or new router for IP camera setup with old Airport Express

Hello,

I am trying to setup a third party Foscam IP camera to my network so that I can ultimately use it as a baby monitor, and am having some difficulty. I currently still have an old Airport Express (with one ethernet port only). This is preventing me from setting up the initial camera because I don't have another ethernet port to plug it in to on the router. I am wondering if I can just buy an ethernet switch and have it "split" the ethernet from my modem to both the camera and the Airport (I do need to check with my ISP provider if they give me two separate IP address... but if they do, would this work?).

I am fairly sure however, that my ISP provider (comcast) only provides one IP for my account. Does this mean I would have to buy a new router altogether with more than one ethernet port on it or one with a WAN port? Would I, in this case, have to plug the modem into the WAN port on the router, and then the camera to one of the ethernet ports on the router?

I consider myself fairly tech savy, but when it comes to routers, IPs, LAN, WAN, etc. I get a bit lost. This has been creating quite a headache for me and any help would be appreciated! Thanks in advance!