Airport +iBook G3 Cannot use wifi

The wifi on the G3 is so ancient it will not work with any modern airport.

I suggest you buy an ancient apple airport. These are pretty easy to find. The last of the discus types.

Plug it by ethernet to your main wireless router.. and setup B+G wireless with WEP security.

Please NOTE.. you have just created a huge hole in your wireless security.. WEP is not secure.. any kid can download a script and crack it. So I recommend you do this for the 5min you need to prove your ancient of days Macbook can connect then turn it off again.

Apple long ago removed WEP as a security option since it is no longer a security option at all.

Apple warn against using WEP security.

AirPort: Joining an encrypted WEP or WPA Wi-Fi network - Apple Support

The G3 early cards only support WEP. Please correct me if I am wrong.. I think the G wireless cards in G4 did support WPA but not the early ones.

Apple stopped supporting WEP in the latest model AC airports.

It is possible to configure the older airports.. ie Gen1-5 with WEP by holding down the option key.. and then selecting the security..

However this will cause all your wireless devices to then drop off the network.. I do not recommend doing it.. which is why I suggested buying the older G wireless extreme.

You will find the requirements for WPA (not WPA2) here:

AirPort Card: When You Can Join a WPA Network - Apple Support

With an iBook running an earlier operating system version, one would be limited to the WEP protocol mentioned by LaPastenague.

A USB Wi-Fi adapter with WPA/WPA2 support is not an option in this very case, since that would require special driver software (and typically at least Mac OS X 10.3 or 10.4), and the speed through a USB 1.1 port would be relatively low.

You could use an external wireless Ethernet bridge (also known as a gaming or media adapter) connected to the Ethernet port of the computer. Netgear WNCE2001 and Linksys WET610 are merely two examples. Some Wi-Fi range extenders (with an Ethernet port, such as TP-Link RE200) may also have similar bridge capabilities. A wireless Ethernet bridge does not normally need special drivers, and can thus be used under almost any operating system. Modern devices should support WPA/WPA2 security (check the specifications before you buy). However, for space, power and portability reasons, it may not be an optimal solution for a notebook computer.