I still use my 3400 regularly. Get yourself a MacWireless 11b PC Card:
http://macwireless.com/html/products/wireless_cards/11g_11b_cards/11bPCCard.php
I've had mine for years.
Yes, they're a tad pricey, but there's no tweaking, hacking or driver-searching. Install the software, plug it in, and it works. Works well.