I'm getting many different hits for that amp name, but all the specs seem similar. You'll probably need to go down the car speaker route, as your amp won't deliver enough power for conventional 8 ohm bookshelf speakers, most have a minimum higher than your amps output. Car speakers (I think) are 2 or 4 ohm, so you'd should have enough for those.
I don't know much about building speakers, but the majority of the cost of hife speakers is the cabinet. A good, strong, sturdy design is best, with plenty of acoustic foam inside to absorb resonances.