In order to get on a network, you'll need a PCMCIA network card, for example a LAN+modem card will let you connect from home via telephone line and from your office or lab via ethernet. The kernel needs to be configured for such purpose: citing from the PCMCIA-HOWTO:
When configuring your kernel, if you plan on using a PCMCIA ethernet card, you should turn on networking support but turn off the normal Linux network card drivers, including the ``pocket and portable adapters''. The PCMCIA network card drivers are all implemented as loadable modules. Any drivers compiled into your kernel will only waste space.More about recompiling the kernel in section 7
If you want to use SLIP, PPP, or PLIP, you do need to either configure your kernel with these enabled, or use the loadable module versions of these drivers.