First, for a personal computer, is the phrase "power transformer" often used
interchangeably with "power supply"? Below I am assuming yes.

I purchased a Gateway Essential 900c in September, 2001. I get a fair amount of
crashes (freezes; requires shutdown; reboot with scan) with it. A friend told
me Gateways were notorious for having poor power transformers.

In others' experience, would it be worthwhile to replace the power transformer?

What's the identifying information on the transformer (so I know what to ask for
at a shop)?

About how much should the transformer cost?

Where is it located inside the casing? (I'll also start researching this on my
own. I have had the computer apart for cleaning before. I'm pretty handy and
have a decent mechanical and electrical background.)

What's a good place to buy a transformer?

Might E-bay have these transformers?

Thanks in advance.