Hi guys, this is a new thing for me-- potentially selling things. I will fit as many things into one package so that if you buy more then one item, I will be able to knock a few dollars off of shipping.
cheers
bird.

Find the Flat Rate shipping boxes at the post office, they are usually the best deal and they are free.

The padded envelopes are strong & hold a lot & only $5.95 shipping.. but hard to find, many Post Office don't stock them..  $5.95  More Info about Priority Mail® Padded Flat Rate Envelope
Priority Mail®
Padded Flat Rate Envelope
12-1/2" x 9-1/2"

The USPS flat rate boxes are my favorite. The boxes themselves are free, and different sizes. I especially like flat rate boxes because as long as its under 70lbs you don't have to worry about weight.

Thanks for your help. Does anyone happen to know the best way to send a wrench to Canada?  I agreed to sell a wrench to this guy for 20 dollars shipped. Of course, I failed to realize the guy was in Canada.....  my own stupid fault. Obiviously, I'm not going to back out of the sale. But, if anyone has any input let me knowQ!
cheers
bird.

Not too tough. Package it up neatly and take it to the post office. The short customs form will usually do, if labeled as a used tool.

under 4 lbs,send 1st class.
your buyer should have let you known he was in Canada,in a case like this i usually do a fair calculation on what the domestic shipping would have been,then have the buyer make up the difference for international...

Its probably not as bad to Canada as you fear shipping 1st class.
  If it is, just ask your buyer to help you. Everybody in Canada knows the score.
They're all too aware of the score.
  If the postage is high and they expect you to stick to the original deal?
They are trying to take advantage of you.
    Because they --all-- know the score.

     Meanwhile the flat rate envelopes are the very cheapest domestically, by far.
The real trick is to cut cardboard the size of the envelope and get some cheap zipties.
(they have zipties in the dollar store now)
   Ziptie your tools to the cardboard and you can mail a tremendous amount of weight in an envelope!
Tying to cardboard is how they ship new tools around the world, and about a million other kinds of products as well.  Look in any store, anywhere.
     
5 bucks and change, insured, tracked, verified shipping.
  Beat that.
     yours Scott