Yodobashi (and Bic) will have pretty much all brands, (current) models, new lenses, etc. This includes mirror-less and compact cameras. They also have filters, bags, tripods, etc. (Yodobashi seems to carry more stock than Bic).
If you are looking for DSLR lenses, there is a "camera outlet center" in the underground level of JR Osaka Station. (I'm sorry I don't know the name off-hand, but I will check next time I head into Osaka). They have most Canon lenses "new" (I haven't seen any of the super-telphotos there, but pretty much all the more common focal lengths, tilt-shift, etc.). The prices are competitive with the big camera stores, and they have a fairly large selection of used lenses. (My own experience: I did not find the savings on the used lenses compelling and wound up paying a little more for new versions of the lenses. However, if you are buying multiple lenses, it might make enough of a difference). This store also sells used camera bodies (digital AND a huge stock of old film SLRs).
That camera outlet center is not the place to go for mirrorless cameras though--they sell a few kits, but at least the last time I was there they didn't have many lenses (new or used) for any of the systems.
Some of the old guide-books might talk about used camera shops in "Den-Den Town" (another part of Osaka). However, over the last few years all the camera shops in Den-Den Town have closed and it has become an anime / manga zone. If you are interested in anime by all means visit--but don't waste the time going there specifically for camera stuff because there isn't any.
Finally, if you are interested in Nikon, there is a Nikon Outlet Center at the "Sanda Premium Outlets" just north of Kobe. You can do a Google search for "Sanda Premium Outlets" for directions, etc. I only visited once about two years ago, but I wasn't familiar enough with Nikon pricing to draw any conclusions from my visit. It is kind of far from Osaka and Kyoto, though, so I wouldn't make a special trip there unless you are really keen on Nikon.
Hope at least some of this is helpful; please let me know if you have any questions, and I'll see if I can find out the name of that "outlet center" in JR Osaka Station soon.