The cost of an ipod microphone will differ. It all depends on the quality of the microphone you want to purchase. Price will range from 10 dollars up to about 50.
Cydia costs $9.99 on iPod touch.
The iPod Touch 8gb costs 199$
$600
199.99
nothing
364.34
189.00
$259.99
360.25
About $180.
About $115.00