Mine came from rs-online, though I seem to be the only one in Singapore who got one from them. They appear to be perpetually out of stock. I can't remember the cost but it came without anything other than the board.
For Arduino a couple of us support sgbotic, which is no more expensive than adafruit or e14 and has the benefit both of being in Singapore and supporting
hackerspace.sg and local educational instutitions with free kits.
Other parts I tend to order from rs-online, just because they'll next day courier even 15c worth of capacitors alone for free (and accepting credit card payment for that 15c.)
e14 is fine too if you're ordering enough for free shipping or otherwise live near TaiSeng and don't mind picking it up - I'm not sure they do same day trade counter pickups anymore (might be next day) but at least when they did it was painless and near the MRT, unlike RS's current trade counter.
Sometimes it just boils down to who has the item in stock and can get it to me before the upcoming weekend. With gst exemption, volatile fx rates and conversion surcharges on sub-$100 purchases, all the extra costs and savings tend to even out over time.