Is there available for iMac OS X version 10.4.11 700 MHz Power PC G4 a wireless keyboard and mouse combo?

All the keyboards I'm finding require built-in Bluetooth, something G3 iMacs don't have. So you'd need to start with a Bluetooth USB adaptor like this:

http://eshop.macsales.com/item/IOGear/GBU321/

Its specs says it works with Mac OS 10.3.9 or newer. The you should ba able to add a wireless board and/or mouse IF you find one that has support for a Mac OS level older than 10.5 or an Intel processor. Most current boards require 10.5.8, and Intel processor, or both.

The cost for all this could easily be 4-5X the used market value of a G3 iMac so please think this through carefully. A long USB extension cable might be a better option fo such an old computer.

The original Apple Wireless Keyboard was released fairly early in Tiger's reign. The current production keyboard allegedly requires Snow Leopard.

If you can find an original Apple Wireless Keyboard on the used market, it will work with your PPC Tiger iMac. Search for the US order number MB167LL/A. The mouse that will work is M9269Z/A.

I used to have this setup with my Mini G4

http://www.amazon.com/Logitech-Cordless-Desktop-Laser-967664-0403/dp/B000E204LY

It's USB wireless, Both run from the same transceiver.

look at this page http://support.apple.com/kb/HT3917