Problems Configuring Two Routers in Different Subnets

My home network configuration is shown below:


(WAN port)
Internet<-----Netopia Model 3346N DSL Ethernet Switch
|(LAN port)
|
16-port Netgear Switch
|
|
----------------------------
| |
| |(tried WAN & LAN ports)
Windows/Linux/FreeBSD/Solaris/Mac Linksys WRT54G Router
(public static ip's) (192.168.1.1) - private
(no available ip's remain (255.255.255.0)
on this subnet) (DHCP turned on)
| (LAN port)
|
Mac 7100 (OS 8.6)
(192.168.1.100)

The public static ip subnet is working flawlessly,
however there are no available ip's remaining on
the subnet (14 ip's), and little chance of obtaining
more from my ISP.

I am attempting to add one more machine (Mac 7100,
OS 8.6) to the network using a Linksys router and
DHCP (wireless turned off). The Mac is able to obtain
a private static ip, but I do not know how to configure
the routers to see each other, since they are on
different subnets.

The Mac 7100 on the private subnet can ping the
Linksys router, but can not ping the Netopia router's
"inside" gateway address, and therefore can not
see the Internet.

Machines on the public subnet see each other and the
Internet, but can not ping the Linksys router.

uPnP: off on the Netopia, on on the Linksys.

I have tried using either the WAN or LAN port on the
Linksys to get to the Netopia, without success.

Question:
1. How do I configure routing tables on these routers
so the subnets can see eachother? I can not find
a way to manually configure the routing tables on
the Linksys, and have not done this before anyway.

I have dynamic routing turned on, but the routing
table on the Linksys only shows the private
Linksys subnet.

Barry Skidmore