Looking for a good online store that sells dependable batteries for my 8320. Thanks.

Seidio.com is always good start and sells reliable products widely used by plenty of folks here.

Several of the sponsors here, seido being one, another is HorizonWirelessOnline.com - Horizon Wireless, Canada’s Cellular Repair Center ß

i've used ShopAlmostFree.com for OEM RIM products. great customer service, good selection, and no counterfeit junk.

as for lithium ion batteries, i prefer to buy them in person, even if i have to pay full retail prices. why? because LiIon batteries have very poor shelf life depending on storage conditions. if stored at over 77 degrees fahrenheit, they will irreversibly lose 20% or more of its capacity in one year.

a battery that's being power cycled, or otherwise being used, will not encounter this... but a battery that's sitting, immediately after manufacture, will.

buying locally allows me to check the manufacturing codes/lot numbers to ensure i'm buying a fresh battery.

this is also why you'll see a LOT of batteries for cheap on ebay or other less than savory parts retailers... they're not knockoffs, they're usually past their shelf life and were snatched up for pennies on the dollar, only to be resold at significantly lower prices ($3-10). only problem is they're usually several years old, have never been power cycled since manufactured, and probably have lost over 25% of their capacity which is not able to be recovered.

oh ya, a reference to my claims about storage degredation: Will Lithium-Ion batteries power the new millennium?