I was in a similar situation about six months ago. Before I bought my tablet, we had a home network with two desktop PCs (each with a NIC - network interface card) and a printer wired to a Linksys hub/router that was then wired to a broadband modem that was connected to our cable/broadband service.
When I got the wireless Linksys hub/router all I had to do was move the connections from the old router to the new one for the PCs to continue to be wire connected. I then followed the router instructions to define a new user on the network for my wireless tablet, making sure to also set the security features for it to keep it secure from intruders.
The new wireless router was about $25 and the NIC cards were about $12 each when I bought them.
The hardest part is understanding the supposedly plain English instructions to set up the wireless user and security.