Need Help In Buying IPOD mini/nano

[M0n3y0nf1r3]

So for this Christmas I told my dad I would help him pay/purchase an Ipod mini/nano for my sister. I really need help in purchasing this becasue I am clueless in a few of the areas and I am coming up short when I research over the two.
1) What is the difference between the nano and mini?
2) Where would be the best place to purchase either of the two via online or at best buy?
3) If it is best to order offline are their any coupons that you would know of to reduce the price or give nice addons? (Ive kinda skimmed the site but I am not fatwallet inclined)
Any and all questions, comments, and suggestions are appreciated.
Thanks,
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