source for reed switches and magnets?

Try:

http://www.goldmine-elec-products.com/products.asp?dept=1189

http://www.allelectronics.com/make-a-store/category/700350/Switches/Reed/1.html

http://www.allelectronics.com/make-a-store/category/370/Magnets/1.html

Radio Shack should carry the earth mags that are small and can be mounted to the back side of wheels to trigger sounds. You can try Phoenix for the reed switches. Later RJD

I prefer the flat CH405-ND from digikey.com.
This unit has 2 mounting holes and PC standoff hardware can be used for mounting.

No glue necessary and they fit on track ties. Black color, normally open and more than enough voltage and current ratings for our trains.
Sealed and weatherproof!! cost is only 30 cents more than the round version. Quantity discounts available.

http://media.digikey.com/photos/Cherry Switch Photos/CHERRY SWITCH-MP201801.jpg

Model 402 is the round version.

I like this place for magnets. http://www.kjmagnetics.com/
Fast service and a great selection of all types of magnets.