no no no
You cannot buy wireless G cards from Apple which support the older PCMCIA slot of a Ti Book or G3 Book.
There are only two companies (that I know of which sells compatible OS X 10.2.6+ cards.
Sonnet and Gigadesigns. I have the Giga in a PB wallstreet and it is fully supported (no drivers needed) under 10.3.7. I also have a Linksys which has the correct chipset (broadcom) but it is no longer sold.
Apple only sells the ALU powerbook G cards these days.