How to approach seller of damaged amp

I received amp via Fedex damaged, but the packing is poor at best, flimsy box, amp covered with plastic grocery store bag and a piece of cardboard on top and bottom. Now I am sure this does not meet Fedex packing standards (deny claim) and I feel the seller shares some responsibility. Ideas? I would just like to return (i abosrb shipping cost and seller sends $$$ back) it and null the deal does this seem equitable?
Yes, your propose solution sounds reasonable. But first, is there a reasonable way to repair the amp at seller's expense w/o re-shipping, etc? You might even offer to pick up the first $X of the repair cost, X= cost of return shipping.
It is always seller responsibility to ship item safely to you. Audiogon rules state that if item gets damaged through shipping seller should return your money ASAP.
Check Audiogon rules.
I received three items damaged in the shipping from Audiogon members and never had problem with getting my money back.
Thanks Darius.
An aluminum baseball bat across the knee caps might produce the desired result.

Never ship FED EX or UPS Store!!!! Ever, they ain't UPS, and they Ain't Fed Ex. If their is damange and if you take the insurance, your hosed!!!! Period.

I pretty much know from the packing that any carrier will deny the claim, I would(would u wrap an item in 1 plastic grocery bag?), my problem is not with the carrier, but with the seller. What approach and results can I expect. I have not tried the preamp but the face plate is crushed on a corner, now should he be forthcoming and replace the facepate? I would like him to take it back if he would not replace the plate. Is that asking too much!
Here's what I suggest you do:

Stay at arms length. The shipping company will ONLY work with the shipping party (ie not you). Use this contract to your advantage. Inform the seller of the damage. Send pictures of the damage, and describe it in detail. I would NOT assign blame. Simply state the facts and ask him/her to inform you of what to do to help them remedy the problem. If the amp appears to be beyond repair, say so. If you would like to return the amp and be done with the transaction, say so and explain your reasoning is that the amp is no longer of interest to you in it's condition. Be patient, objective. and persistent.

If the seller says it's your problem then you're into irrational territory, and you'll need to argue. If you have any way to get your money back (ie Paypal buyer protection, etc) you'll need to do so.

I've been in similar situations more than once, and the strategy in my first pragraph has worked because the sellers have operated in good faith. But I NEVER told them I thought their packaging was crap, even thought it was.