You can get a basic for about $40 for minimal coverage or go into a hundred or more dollars with more powerful units that have multiple antennas.
Linksys, Netgear and D-Link are the top brands.
I would do an Amazon search for routers. Look at the prices and read the reviews. I would love to recommend something specific to you, but models change all the time.
Another thing to consider is that where all the ethernet cables converge is often not the best place to have a wifi access point. A standalone access point gives you that flexibility.