combo wireless and wired home network

[Harry Putnam]

Before getting in to deep, I'd like to hear a few comments on how this
could be done:

I have no wireless experience so may have the lanquage and concepts
  somewhat askew...

  I want to use a wireless connection for 1 computer on my home lan.

My machines (5) sit behind a NETGEAR dsl router/firewall.  Everything
is currently cat 5.

I want a wireless hookup behind the router.  Some thing like: 


                INTERNET
                  |
                DSl MODEM
                  |
          NETGEAR Router/firewall
          |                  |
         M1                 M2
                            .
                            .
                            .
                            []
                            M3 

Where M2 is setup gatewayed (hardwire) to NETGEAR ROUTER and is itself
a gateway (wireless) for m3.  So it needs a regular nic and something
that makes a wireless accesspoint.

Is there such a thing as a pci card that is a wireless accesspoint?
Or maybe M2 needs to be an actual hardware wireless router.

M3 is a laptop that I'd like to be able to connect to the lan from
anywere around the grounds.  Like in the garage or etc.

Its an older Tosh 4005 but I'm guessing somekind of wireless nic
exists for it.