I built one several years ago, but I no longer have the schematic. instead, i found **broken link removed** on google. As far as the output device (an 8ohm speaker) is concerned, it looks somewhat like the one I built. I didnt however simulate this circuit.
:idea: If you have a copy of or can access a copy of the "Basic Semiconductor Circuits" volume of the Engineer's Mini-Notebook series by Forest Mims III (Radio Shack may still carry these), there are a couple of metronome circuit schematics provided. They are very simple and have a low parts count which is always a bonus.
if you have any experience in using the 555 timer, you can use this. just connect a simple amplifier circuit, say in darlington fashion for the output.
as an added suggestion to my previous reply, you can also use a Johnson decade counter CD4017 to lite up 8 LEDs to indicate the beat. eg. 2 lited LED means a measure of 2/4
just connect the output of the 555 to pn14 . connect 8 LEDs to the output of 4017. use a 2pole 6 position rotary switch to activate the number of LEDs to light. connect pn13 to ground, connect pn15 to rotary switch