Agreed, you'll find the web is an awesome resource...and an awesome aggravation. Even if places show things out of stock, revert back to the good old fashioned telephone. Find out if they are really out of stock...make friends with parts people so you can get first dibs on things when they do come in stock. Pay extra and get some things at the local dealer and get to know the parts people there...making friends at places you buy stuff is great because well...you get more friends, and friends help each other out. Just make sure it's not a one way street or those options will dry up fast.
Research, research, research...who knows some guy at the dealer might be a SOHC freak and have a stockpile of stuff he can sell you or trade or whatever...or he'll have a secret stash of sohc stuff like a guy at my local shop does because the guy who used to run the shop was into them bigtime and had a chopper with a cb750 motor at one time. How I got my gasket set and my Accel coils and wires for cheap lol.
A lot of it is being in the right place at the right time, or just plain spending hours online searching through all the crap to find what you need.