Ipod Touch 4th Generation?

So i had an Ipod TOuch 4th Generation, but it got wet one day. So i have been saving up for a new one and I have 90 dollars saved up. And my mom said that she would put 50 dollars towards it, So i have 140 dollars saved up. But can also dip into my saving funds and get any money i want out of there, but i dont know if i should. Its the summer time right know so im not worrying about it. But when school starts up again, I would like to have one. So i was thinking that i should check ebay or amazon because they have some used, or new ones for sell. So should i get one from an interent shop or wait till i go to walmart or Target or Best Buy.