Telescope accessories in Atlanta?

Yeah, unfortunately Camera Bug was the only place I ever found that carried scope gear. It closed a couple of years ago after the owner passed. You might want to send an email to the Atlanta Astronomy Club. Maybe someone there knows a place locally.

That said, and since you mentioned the Perseids, a Barlow will be more of a hindrance than a help for meteors, as it will dramatically limit your field of view. With meteor observation, field of view is far more important than magnifcation. A decent pair of 7x35 binoculars is more than enough, if you use anything at all. I've had a great time just laying back on a pool lounger and watching the sky.

You might check Showcase photo, but Camera Bug was the place to go.

If you're concerned about shipping to your apartment, can you ship it to work or to a friend?

Camera Bug was great. I miss the old mom-and-pop shops where you walk in and just see piles of unorganized boxes and gear, with the owner in the back tinkering with something. I bought a telescope there and it took the guy like 20 minutes to find all of the parts that should be included. But he threw in a bunch of other stuff, gave me a lot of tips, showed me how to use everything. I went in a few months later to ask about hooking my DSLR camera up to my scope and he totally hooked me up. He showed me exactly how to connect the adapters and how prime focus works. You won't get that kind of service from Best Buy or Frys or some other big electronics store where the sales associates don't actually know anything about what they're selling or have any interest in their products.

A bit of a late response... I'm into astrophotography and astronomy, but don't have anywhere local to buy stuff either - but I used to buy from an awesome store in Damascus, MD, when I lived in Northern VA/DC. I realize it's not in any way local, but they are awesome and do quite a bit of their business via internet. I bought my 5" Celestron NexStar 5SE computerized telescope from them in 2009, as well as most of my optics up to about mid-2014. I've since been buying via amazon and directly from celestron.
http://handsonoptics.com/

Celestron lists the only authorized dealers in GA (usually a good way to find telescope/optics stores) as being Fry's in Duluth and Alpharetta, so I'm going to guess that there really aren't any more telescope stores in GA at all (which sucks!). I've seen the telescope selection at Fry's in Duluth and wasn't impressed at all. Most of the stuff they sold there was entry level and not very high end.
This isn't that surprising though - between the internet, light-pollution, and reduced popularity of the hobby, I guess it makes sense. Celestron did point the way to two potential dealers, one in NC and one in AL, depending on your willingness to drive a bit. The one in Asheville, NC seems like the better bet, as the one in AL looks to only carry accessories and maybe not actual scopes.
Clanton, AL: http://www.opticsmart.com/
Ashville, NC: https://compleatnaturalist.com/product-category/optics/telescopes/

Last, but not least - the hobbytown in Kennesaw recently had a couple entry-level telescopes and some gear, but again, not a very impressive selection.

PS - Last again, a barlow would probably not be the type of lens you'd want - instead a wide-angle FOV or a great pair of binoculars.