I've been eager to purchase an AirPort Extreme Base Station for quite some time now, but would the network extention work with, lets say a comtrend Wireless router?
if not go with maybe another comtrend or something
Just to be clear (since you reference both) the Airport Extreme Base Station doesn't support AirTunes (it does however support external hard drives, printing, using a powered USB hub to more of either or both, and 802.11n).
The Airport Express on the other hand has AirTunes, can support a single printer, and is significantly cheaper. No 802.11n, shared drives, and only one printer though.
It sounds like you are after the Airport Express, I just wanted to clarify since you mention both.
Just to be clear (since you reference both) the Airport Extreme Base Station doesn't support AirTunes (it does however support external hard drives, printing, using a powered USB hub to more of either or both, and 802.11n).
The Airport Express on the other hand has AirTunes, can support a single printer, and is significantly cheaper. No 802.11n, shared drives, and only one printer though.
It sounds like you are after the Airport Express, I just wanted to clarify since you mention both.