I have a Technics SA-160 receiver. It has worked great for a number of
years, but now it does not start.

I was thinking it was a fuse that went out.

Does anyone know how I would tackle this?

I think it may be as simple as changing a burnt out fuse.
Thank you in advance for your help.

It may be a fuse. But fuses usually blow for a reason, and replacing
the fuse without first checking for shorted components can cause
secondary damage and more cost. Check for shorted output transistors or
ICs, power supply diodes, and filter caps first.

Another possibility is an open power transformer. The thermal safety
fuse inside the transformer may fail, due to lightning or a power
surge. If the primary reads "open" this is your problem.

Good luck!

My background is not in electronics.

Is there a "step by step" method for doing these things on the web?

Do I need special tools for diagnosing these problems? I don't have
any.

Without test equipment and some familiarity with these things, your
safest and easiest solution would be to find a service facility who can
give you a diagnosis or estimate, fairly.