I use a "snaking trick" that is pretty effective in these situations. I know you said "besides snaking" but I dont know how you could avoid it (besides surface wiring).
I take a roll of mason's string and tie a heavy nut or screw on the end. I then dump a pile of string into the wall cavity (the string just falls into the wall space by gravity). I then take my metal fish tape and grab the string from the other end.
I'm sure you have all heard of this trick but for anyone that hasn't, it can be a real lifesaver. It's really great when working alone.
#17220 - 11/21/0211:44 PMRe: adding circuits to a panel that is not accessible
What I do after running romex into the panel is use a plastic romex connector, the type that has a small wedge to secure the wire, and put it on the wire backwards, then I snap it into the knockout from inside the panel. Now the wire has a secure safe connection. No one ever said these connectors had to be on the outside and it eliminates the problem trying to get a locknut on a metal connector. BTW my fiberglass fish-sticks are a lifesaver doing this type of work!
[This message has been edited by gto6t7 (edited 11-23-2002).]