Does any one know where I can find a printer that is suitable for light traveling and capable of printing documens on a4 paper

At the computer plaza on the left hand side of the road as you come back from Doi Suthep (Huay Kaew rd.) and hit the moat, it's just on the left.

---or drive around the outside of the moat until you pass CM Ram hospital/Sri Tokyo Hotel, turn the next corner of the moat and it's on yer left-about 50 metres down.

- it's possibly your best bet.

Pantip Plaza

Night Bazaar road :

go down loi kroh road to its end, turn right past Mcdonalds... past Anusarn market, and it's on your right..

I'll soon be looking to buy a printer too - not necessarily a portable/travelling type. Do these specialized places have better prices than the department stores (central, robinson) or even carrefour etc? Of course I assume they would have a bigger range. Later models?

Any large store really is ok... but Pantip Plaza and the collection of Computer shops along the moat road mentioned earlier are your best bets...

IT City in Pantip Plaza is where i bought my Canon iP4200 for 3800 baht just a couple of months ago.. and a darn fine printer it is too. Not the latest, but as good as...

I'll soon be looking to buy a printer too - not necessarily a portable/travelling type. Do these specialized places have better prices than the department stores (central, robinson) or even carrefour etc? Of course I assume they would have a bigger range. Later models?

Yes.