So I recently got a Peavey 5150 combo, and the guy I bought it from had a family that smoked. So now the amp reeks of old smoke. I hate it, because I'm very against smoking.

Any tips on removing the smell quickly and permanently? I'm going to try putting the dryer fragrance sheets and cover the amp with a blanket, think that would work?

and is it okay to spray lysol/oust on my amp? I'm afraid it will ruin it somehow.

this same situation came up about 6 months ago and i think the result was:

Febreeze the h*ll out of it.
replace tolex or otherwise.
scrub inside with lemon pledge (wood only unplugged)
burn inscense inside cab and rid demons.

or something like that...
will the febreeze or anything ruin the amp from the moisture? I'm pretty concerned with that... like if it gets on the tubes or the circuitry or even the speakers...
Most of the scent is probably in the wood of the cabinet. If you feel safe pulling the chassis, take it out and see if you can scrub the scent out of the cabinet. Of course if you don't feel safe pulling the chassis and speakers, then don't.

Do NOT get any of the electronics wet. Tube amps have the tendency to store voltages.
Maybe some of that Electronics spray cleaner stuff....we use it at work, and you can actually spray the stuff on circuit boards and such to clean up gunk and other residue. As for the cab it self...Good Luck, I doubt you'll ever get it completely odor-free of the smoke. I think the smell gets into the wood grain.

I once had a guitar, I bought off ebay, smelled like smoke really bad so i never played it, kept it in the case in another room even. I eventually tried cleaning the heck out of it. I tried everything I had around the house, lysol, pledge, febreeze, dryer sheets, 409...I finally decided just to strip it down and re-paint it. That worked! lol..
I got a free amp a few weeks ago when I bought a guitar and it stank too! Couldn't give the thing away....