@Virgin Megastore has the best items to buy as well as @Carrefour i bought my mobile from there.. You can also check this site they have items on sale http://www.mobibuyer.com/..

Where can I find a hoverboard?

Check out @Virgin Megastore as well

Where can I find the Amazon card to use on Kindle?

I bought one from @Virgin Megastore

Where can I find a good quailty headphone splitter?

You can find really high quality head phones at @Virgin Megastore in any mall

Where can I buy Zoella products?

I bought some of Zoella products from @Virgin Megastore :D

Where can I buy a ukulele?

You can find ukuleles @Virgin Megastore

Where can I get a high quality selfie stick?

@Virgin Megastore they have selfie sticks

Where can I buy Indian movies?

You can find a few @Virgin Megastore mostly the recent releases

Where can I find an iPod 5 in Dubai Mall?

@Virgin Megastore

Where can I buy One Direction perfume?

They are available @Virgin Megastore

Where can I buy a studio quality condensor microphone?

@Virgin Megastore

Where can I find a good guitar tech to setup my guitar?

@Virgin Megastore

Where can I buy a really good amplifier for my electric guitar?

If you want a cheap on check @Bose or @Virgin Megastore

Where can I buy a small musical keyboard that's reasonably priced?

try the various music shops in Dubai mall including @Virgin Megastore