Orange: through google I did find a couple places, most however appear to be Harley type shops. I live in Amador county and just by looking out on a weekend I can say that Harleys outnumber everything else 10:1 here I can see the lights from Modesto from my house at night, but its much further than Sac so I prefer Sac for that reason.
What type of accessories specifically? PCP motorsports in Elk Grove (across from the carcass that used to be the Florin Mall right off the 99) has a shop with some things. They did not impress me with their vast selection, but they did have helmets (street and MX), gloves, pads, boots, jackets, and the like. They also had some limited gear for bikes.
Knowing what type of accessories you want could help a bit in figuring out what store would be better
@KMWilliams: the intarweb is for after you have figured out what you want, then you look for the best price, read reviews, etc and if its cheaper order there
I discovered that there is a cyclegear.com in Sac. It is just off the 80 just north of Madison (citrus heights area). It seems like a fairly large store, and given the size and scope of their chain it is likely that if its not in the store they can get it (or you can order online). They also have one in modesto and many other places around this area. That may be the best choice.
I just looked at yp.com and after several attempts to find something discovered them. I plan on going there, if no one else posts anything I will give my impressions.
forgot to post this, I went there this weekend. IIRC its 5400 Date. Nice sized store, lots of gear. There is even a "HD" section (the type of gear many of them seem to wear, black leather vests, half helmets, etc). The staff is friendly, I liked the fact that when I went all the girls working there were in costumes that were quite flattering to them
The road going in can be a bit rough, even in a truck it seemed like it was not a smooth ride, just a bunch of potholes and such. Fortunately its not a busy road and the road really only serves as an entrance to the store so there is no pressure to go swiftly.
I would imagine that their stores in other locations (dozens of them between Sac and Modesto and SF) are similar in content, size and all that.