Hi Cessylicious,
I've been twice. 99 and 03
The thing about Bangkok is..that it's unbearebly HOT..most people can't stand the heat for more than 2 days..so it's smart to economize your time and have a clear picture of where you want to go and what you want to see/buy.
You haven't mentioned what price range you are looking for, because I think Bangkok is best for the incredibly cheap.
Bangkok is a knock-off heaven if you're into that (you just have to know how to bargain..) If you are into the real thing you HAVE to go to the flagship stores..anything outside the flagship stores..I wouldn't trust.
You'll more than likely need transportation around Bangkok..and taxis, tuk-tuks and Rickshaws will take you to your destination for next to nothing..but there is a hatch..you
juuust have go and visit an number of stores on the way there..that give your driver petrol-vouchers if you buy some of their overpriced products
IT'S A HASSLE! ..and some of the drivers wont even take you unless you agree to visit those places beforehand..just get out...it's a timeswallower and once the novelty of it wears of..it's annoying for both you and the driver!!
If you stay by the river, take the river..or if you are close to the metro (? can't recall the name for it) take that.
Do your shopping in the morning (difficult since most stores doesn't open till 10am
) or later afternoon/evening
Sight seeing is generally best in the very early hours..but if you decide to see the wonders of Bangkok from the river Chao Phraya...do it mid-day...the river will be the only bareble place to be except a/c places like generally boring malls.
Really Cheap stuff
Khao San road marked ...backpackers heaven (see the links below..some of them describe this marked)
The Patpong Nightmarked... if you are into copycat wares.. like LV bags etc..it's NOT for the delicate souls..Patpong is part copy-marked / part flesh marked.. and despite the fact that you might be walking with your boyfriend/husband..you'll both get offered "pin-pon-shows", giggolos, or "massages" via a "menu card" stuck in your face etc.
Glasses - designer frames and perscription glasses (but ofcourse that demands that you are in Bangkok more than 2 days)
Thai silk
Jewelery is supposed to be cheaper..but it's a REALLY tricky business with lots of fraud..
Made to meassure Not to be done if you are only there a short while, and frankly I'm not sure I'd do it even then..because I've never seen a result that looked really great..
Malls carry mid-range brand names..but normally nothing fancy.
You can get Scholl products for next to nothing in the shoe departments (great if your feet tend to cause problems in sandals and the heat)
You can get Nike adidas etc cheaper..but usually its not the same products as you would find in a northern european Nike/Adidas store...generally the Nike/Adidas sold is marked for the asian marked...and taste.. and so it goes for a lot of brand names imo.
Very high spf sunscreens ..like 50 and 60, and whitening products if thats your thing from label like Lancôme, Estee Lauder etc you'll find in aboundance in the Malls. I didn't find the airport incredibly cheap..so you might want to keep a pricelist of what you usually pay for your favorite products at home..so you can compare to local prices.
Expensive Stuff
Bangkok does have it's own LV flagship store and so does a lot of other luxury brands..they are all situated along the same stretch of road ( the name escaping me right now ofcourse
)
Links I think are worth checking out:
http://www.into-asia.com/bangkok/shopping/
http://www.bangkok.com/shopping/ << check out the section about shopping tips
http://bangkok.thailandtoday.com/shopping/
I hope I didn't make it sound awful..it's actually quiet fun if you are a bargain huntress