An Access Point may have capacities above a true network bridge, such as various levels of network authentication or VLAN trunking ability, but the kind you're likely to run into in the home are pretty much network bridges. They just link two different media types together onto the same logical network. The router-with-wifi devices just have this built into the router, but stand-alone access points are still available (I use one at home for a dead spot).
What you're looking to create is generally called a wireless bridge. The network diagram is roughly...
Internet -> Router -> Wifi -> 2nd Router/AP -> Ethernet -> Your office machine
The two router/APs are configured to be a wireless bridge between two wired networks. Some devices can also still function as a regular access-point in this config, but I don't know how common that is.