Is there a PCMCIA Ethernet card for Powerbook G4 OS X 10.4.8 ?

Just search Google:

http://www.welovemacs.com/net-mpc-100.html

http://macslash.org/article.pl?sid=05/11/09/2132230

How old is your Powerbook?
A Mac older than 4 years old may need its clock battery replaced by an authorized service center. The clock battery dying can cause certain ports to malfunction as well. If it is under 4 years old and no surges broke the port, try zapping your PRAM, it may solve the problem once and for all:

http://www.info.apple.com/kbnum/n2238

If it is under AppleCare, there may be no cost at all. Any Mac under a year old is under AppleCare.

Also replacing the system board can be cheaper than from Apple directly if you take it to one of these places:

http://www.dttservice.com/
http://www.powerbookresq.com/
http://www.microdocusa.com/
http://www.macspecialist.com/
http://www.techrestore.com/

In addition, if the port got burnt out by a storm surge or power surge your home/apartment insurance or credit card company you purchased the machine with may pay for the damage. So check each of those sources if you can't find an appropriate card.

http://www.xlr8yourmac.com/ lists a variety of upgrade cards in their database, and may have some ethernet cards you can look at.

By the way, the fact that port is broke suggests the possibility that any other system difficulty you are having may also be related to logicboard issue in anycase, so replacing the logicboard is a good idea if you are noticing other issues.

This thread may yield some clues:

http://macslash.org/article.pl?sid=05/11/09/2132230

Some ethernet cables may not clip in place because of the cable itself breaking. Try the other end of the cable to see if it clips in place, or yet another ethernet cable.

The best cables are Cat 5 and Cat 6 cables.

Sounds like you'll have to punt and find the right card in that Macslash forum.

Your other option is to add an airport base station and connect the machine wirelessly.

If it's simply the Ethernet port itself that's broken, I can easily replace it alone--no need to replace the whole logic board--for $120 labor. You can contact me (John Sawyer) at CJS Macintosh Repair, 510-849-3730 (Berkeley, CA), or email me at johnsawyercjs(at)yahoo.com, and if you decide to do it, you can ship it to me for repair. My company is one of the first non-Apple repair companies, started in 1985, so I've worked with practically all the various Mac models, and I've replaced many broken ports.

However, look inside the port to check if you can see what's physically broken. Especially look at the contacts inside the port--if they're bent downwards, or just not coming up high enough, the contacts on the Ethernet cable plug may not be making contact with the port's contacts. If that's the case, you can usually fix this by using a small tool like an Xacto knife to pull up on the contacts to bend them up a bit higher. Also run a small eraser over the contacts to clean them up--I use an old-fashioned ink eraser pencil, the type you sharpen in a pencil sharpener, to get into tight places.

Power Mac G4 Quicksilver 2002, 800 mhz Mac OS X (10.4.8) 1.5 gig RAM, two serial ATA drives connected to a FirmTek SeriTek/1VE2+2 card

If you just need a PCMCIA ethernet card, get this one from DLink.

http://www.dlink.com/products/?sec=1&pid=132

It works fine. Don't bother with the driver CD.

You should really try USB to Ethernet.
I have tried a bunch of cardbus cards, none of them were recognized by OS X 10.4.8
Review the site below:
It seems like it has a favorable resutls.
Good Luck

http://sustworks.com/site/newsusbethernet.html