For iPod: Just need dock and this one (Audioengine A5 powered Speakers). In Thai, buy here http://www.enjoyyourmusic.co.th Got a lot of mentionings and reward from WhatHiFi.
For PC system: Going to try Class T amplifier, TrendsAudio TA-10.2 with high sensitivity speakers, perhaps Klipsch. Polk Audio should also be OK. Read this http://bookshelf-speakers-review.toptenreviews.com/ when you want to buy speakers. This amplifier is not too expensive. You can buy from http://www.trendsaudio.com directly. It accepts paypal. This one is very famous. 6moons and many others review it. Got to try this one.