Toyota Repair: 93 Toyota P/U, running power, toyota pickup

Question
Truck info:  1993 Toyota Pickup, Extended Cab, 5-speed, 2WD, V6 3.0L.  Mileage:  253,4??.

Here's what happened:  She's been running like a top lately.  She does have some sort of issue with the spark plugs needing to be changed every 3-4K miles - before they gunk up and cause running/power problems, and the last issue with plugs was around 3K miles ago where the insulation on one plug cracked/broke in pieces - was told due to heat..."?"  Anyway, that's not the issue (that I know of) today...today we have a "she cut out and won't restart" issue.  I filled up with gas after work (mid-grade), drove approx. 7 miles, parked & turned her off, approx. 10 minutes later restarted normally, was driving slower than the 20 mph speed limit...the road was on a slight decline so I was mostly coasting in 2nd gear, then I needed to give her a little gas so I pressed the gas pedal.  In no more than 15 seconds duration, she very quickly went back and forth in acting like she was in neutral then in gear...in neutral then in gear...in neutral then in gear.  Then she just cut off.  And won't restart.  She turns over just fine - mostly normal, there's an ever-so-slight "dragging" to the cranking but that's hardly there.  With fuel injection, I'm used to not pressing the gas to start her, but as she wasn't starting I pressed the gas pedal - only when pressing the gas pedal does she have the god-awful knocking sound that, to my ears, comes from the driver's side.  When I'm off the gas pedal, that knocking isn't audible from behind the wheel, so I don't know if it's going away or just too low for me to hear.  Anyway, a neighbor seems to think the timing belt broke...that can't be right, can it?  There would be no cranking, then - right?  Besides, this timing belt has under 25K miles on it...I realize faulty parts can sometimes just happen, but...

What do you think &/or suggest?  Any ideas on what might be possible things to check out for what might have gone wrong?

I'm not a mechanic...  I wish you could make a decent, honest, trustworthy mechanic appear in Juneau, Alaska - I haven't come across any yet, really...the last place I took her I was told they didn't want to work on this "old POS" anymore...they prefer to spend their time working on the newer vehicles - forget the old ones..."get rid of 'em"...

Is there anything a non-mechanic could possibly check out for this issue?

Thanks for your time and help...

Answer
Hello, I don't think that the timing belt is the problem but can't rule it out, that knocking noise is cause for concern at this time it sounds like it may be a engine bearing, is the oil level ok? Can you tell more specifically under the hood where the noise is coming from? The noise could also be coming from the water pump or an idler bearing at the front for the timing belt, the spark plugs faouling out indicates that it's using quite a bit of oil, have you considered just ordering a used engine and then having it installed, this one sounds like it's getting tired and it may not be worth repairing.