I gave up looking for bargain iTunes vouchers so started looking for something "else", on reading some forums I came across this at first:
FreeAppWin - gave it a try, you enter daily comps to win $50 - $75, so far I have won and claimed $6 at amazon.com.
You can try apps as well for more entries but I have not gone that far, requires +-2min
So I carried on searching on how to earn iTunes gift cards at mac forums.
A google search will bring up the links etc.
AppCasher - currently on 2550 credits - 15000 credits buys you $15 iTunes voucher, amazon vouchers also available.
My referral id - 285520 if you use it we both score extra credits, each time i get 1500 credits people that use my code get credits.
Free my Apps - currently on 430 credits, - 3000 buys you $10 iTunes voucher, amazon also available.
Me referral id - http://m.freemyapps.com/share/email/14123907 if you use it we both get extra credits.
FreeAppSlots - currently on 23,456 credits - cash out and you can claim free apps like Angry birds star wars or wait until you get 160,000 credits and claim $15 iTunes voucher.
My refferal id - http://freeappslots.com?refcode=33pbbssq we then both get extra spins.
you get 10 free spins first install, then 4 spins every day, the easiest app I have found.
These apps don't take up too much time and you will not get $15 itunes or amazon in single day, but over time I'm assuming it can grow.
I assume the quickest way to get dollars is buy getting friends to join etc.
It hasn't taken up too much of my time so will keep at it.
Apologies to mods if this thread is taboo, just thought others could benefit so why not