Ship to USA only?

I'm new to the site and have yet not made any transactions. I've noticed that most sellers on the classifieds are only willing to ship within the US. I live in Toronto, Canada and I'm simply wondering if there are reasons most sellers are not willing to sell across the border. Are there problems with Canadian customs?
Highend, guess yo mamma didn't tell ya soon enuf that excessive alcohol comsumption will rot your brain.
Boy,you guys have scared the heck out of me.When I first read the title of this thread,I was thinking;China,Japan Korea.I have heard storys of long time to deliver.But most all the responses from Canadians,contradicting each other. Of course all threads, on all subjects,usually go that way. WOW, and Mr Highend,COLLAGE,means medley, montage. It does not refer to a place of higher education.But in your case it probably refers to anything past the second grade,as your response indicates.Hey,I got some fire retardant right beside the browser,lets see what you got!! Only a very narrow mind thinks in terms of "all Canadians',All Americans',all Frenchmen" Smart people have figured this out them "selfs" You know I was joking about the second grade before,now I'm sure.You know,a person can walk into a room,all the narrow minded people are thinking,because of his apperance,"boy is this guy dumb! The intelligent folk wait for the person to say something,thus removing ALL doubt. I probably have to explain this to you;but Mr Highend, you just walked into our room.
My sell ads also contain the restriction "sell to USA Buyer only". That is because my payment terms are COD via certified funds. These payment terms are both difficult to apply to overseas transactions simply because it takes way to long to get paid. I also don't want to have the deal hung up by customs or duties or anything like that. However - I have and will sell to non-USA buyers IF they agree to prepay via wire transfer. In fact I have sold items to buyers in both Europe and Asia on this basis. I admit that I'm not sure I would agree to these terms if the circumstances were reversed but I do have a good audiogon feedback record (+48) so I guess buyers are a liitle more inclined to trust me. In fact, my last auctions closed on July 10. One was for cables from a european buyer the other was for a preamp to an instate (California) buyer. I got paid on the cables via wire in about a week after the auction and then shipped them to The Netherlands via 2-3 Global priority. Everything went fine. Shipping cost was about $65 for about 11 pounds. I shipped the preamp to Sacramento (about 400 miles away) via UPS - COD and got paid yesterday (a little more than 2 weeks after delivery). When selling overseas I complete the customs declaration form and its up to my buyer to deal with customs abd duties from his end. I've already been paid in full so at that point it's not my problem. Still think all Americans are dumb Highend? Oh well - I do have two post graduate degrees in addition to my "collage" education - BUT - I did play football.
Glad to hear someone else has had similar experiences to mine in selling outside our borders. I too have a 'collage' education, from Emory U. As much as I've tried, I just can't come up with a better way to put things than avguygeorge already has; he stated things quite eloquently. Would also like to state this: I have two very good Canadian friends who are nothing like mr. highend, so don't let him form your opinion of all Canadians.
The Collage went over your American heads.I guess those COLLAGE grads who cant read and write but can play football,basketball.They would spell it COLLAGE get it.