laptop, aircard internet, sharing network

[kbutlrtech]

ok got a good one for you network guru's... i set up a common home network system using network wizard.. both are xp one is laptop other is desk top..i used a cross over cable for ethernet.. i use a pcmia card for wireless internet service.. i set up the aircard so it is to be shared..all works well.. now i want to add a 3rd computer and hopefully use wireless..so i hooke up a linksys router disabled the wan and plugged both computers in to one of the 4 ports to use them like lan switch network. again i can share files and printer but now cannot share the internet..i also tried connecting the client computer via wireless to the linksys and same thing.. any suggestions