I've only bought from this guy once but the prices are great and the batteries arrived as promised.
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I bought ten Sony CR2016 batteries for a total of $6.90. He has CR2032 at the same price. The local Walmart's prices are four times as high. He also has GE/Sanyo CR123a for $2.29 each if you buy a dozen. You need LR41 batteries for laser pointers? I bought 30 of those for $14.70 total.
He (Adam Librot) stocks other common batteries, Photon LED lights, etc.
USPS shipping is free for orders of $12 or more.
Like I said, I only bought from him once, but I will again. YMMV.
If you have questions, please email me. Work is busy and I don't have time to check m.s much anymore :-(