the speakers being 8 ohm might be a problem....
well for 8ohm speakers which can handle 20-120w...the cheapest amplifier you can get which can power those speakers to decent volumes would be something like this
>this< which is available for $69 or
>this< model for $62.
however, keep in mind that in reality they are only good for 2x50w @4ohm or 2x25w @8ohm before you start getting some rather nasty distortion as they can have up to 10% distortion
to power 8ohm home theater speakers without distortion you often need a bigger more expensive amp.
something like a stereo receiver like this one
http://www.amazon.com/Sony-STRDH130-Channel-Stereo-Receiver/dp/B006U1VH2S/ref=sr_1_2?s=electronics&ie=UTF8&qid=1406661204&sr=1-2&keywords=stereo+receiver which i've seen for $120 can easily power 100w @ 8ohm with 1% distortion (or 10x less distortion).
now, there are certainly other products which are between those on budgets and might put out a little more power then the smaller stereo amps however due to low quality they also have rather high distortion.
basically: if you want to listen at relatively low volumes... you can get away with the cheap option. however, if you want to crank up the volume you would want something better
due to the rather large size of the amps required to power those speakers... as well as the prices for anything half decent it very likely is not worthwhile for you to go that route.
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since you have a very limited amount of desk space......you might want to stick with:
-computer speakers (such as the t20, t40, soundsticks, or other speakers)
-a micro hifi system (basically the style of
>this< system.
since you do not like bass... you might want to stay with a 2.0 set without a subwoofer.