Wireless networking headaches

This morning I setup a wireless LAN at a 3-person law firm in Delaware. Initial setup was pretty straightforward, but it's not what I consider to be fully functional. I could use some input here.

The network consists of three PCs, two eMachines boxes and one Dell, all running XP Home (they had these boxes before they called me). Each PC has a Netgear WG311T wireless NIC which was installed according to the manufacturer's directions. There is also a Netgear WG302 wireless access point. The intented use of the LAN is to share a cable modem connection and allow file and printer sharing among the three users.

The Ethernet interface of the WAP has the IP 10.1.10.2/255.255.255.0. The first eMachines box is 10.1.10.10, the Dell is .11, and the second eMachines box is .12 The WAP and all three PCs are pointed to 10.1.10.1 for their gateway, which will be installed Monday.

Each PC is able to associate with the WAP and signal strength is excellent. All PCs are setup in the same Windows workgroup. No firewalls are running. NetBIOS over TCP/IP is enabled.

I was able to login and configure the WAP by connecting my laptop to its Ethernet port.

Problems:

1. None of the PCs can ping each other or the WAP.
2. The PCs cannot see each other in My Network Places, except that the Dell can see eMachines box #1, although not access its shared folders.
3. With my laptop connected to the WAP's Ethernet port, I can ping the WAP but none of the other PCs. Nor can any of the other PCs ping my laptop.
4. The wireless PCs cannot pull up the WAP's login page in a browser.

WTF? Will this not work until a hub/switch is connected to the WAP's Ethernet port?