Looks to me like you need 3 products from this page :

http://www.wavelan.com/products/index.html#home

1) ORiNOCO PC Card (Silver/Gold) - G/S is encryption levels
2) Ethernet & Serial Converter (Formerly WaveLAN Ethernet/Serial Converter)
3) RG-1000 Residential Gateway

If you buy the startup kit you get items 1 and 3

Empeg becomes a wireless client to the Gateway. The products you need for the empeg are 5v and not too big. Not sure how you would bridge the Gateway to existing Ethernet LAN - although it does mention an Ethernet port on the Gateway.

Have just ordered the kit, so will get photos once it arrives.

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Rod, UK Mk2 64gig Red S/No.341