For all the US traders who ship to Canada, what method works best for you? Also, are you required to fill in customs forms and if so, what do you put on them?

I always declare as "Homemade discs/tapes for pen pal" with a value of "N.C.V." (meaning "No Commercial Value", to continue the "homemade" theme).

I always use airmail letter post. By the way, I just found out recently that when mailing out of the country you don't need to fill out a customs form if the package is under one pound. So I've discontinued this practice. The less governmental control the better.

For packages over one pound I write "computer discs" or "homemade videos".

I just usually state "vhs tapes". When the post office lady asks me for value, I tell her $5 for the cost of the blanks. Every time she asks me what they are, and I tell her that I have a friend in Canada who tapes stuff for me that we can't get down here and vice versa, which is true. I don't generally buy from Canada (on occasion and usually stuff that's in the gray area - not commercially available) and I NEVER sell to Canada.