Ethernet switches, CAT5 or CAT6 cable, and wall jacks for CAT5/CAT6 are relatively inexpensive. Ethernet switches can be cascaded. Depending on how many devices you need at one location, it is probably cheaper to run one cable to an Ethernet switch rather than multiple home runs of cable to multiple jacks at each location. Just add up the cost of cable/foot and the individual jacks with cover plates. You need patch cables also.
An inexpensive punchdown tool and a cable tester would be helpful.
While you could run CAT5/CAT6 cable device to device, troubleshooting is easier with wall jacks.