Hi, and welcome to the forum!

Your best bet would be to find an international shipper of some sort - either an international mover or someone in the business of shipping across the border. The tricky bit is getting your personal effects through customs, and an international shipper will have a customs agent that they use for that.

You can probably ship your goods back to the US without paying customs if you are moving your residence to the US - with either the appropriate visa or if you are a US citizen returning "home." You'll need a list of the items you're shipping, including approximate purchase date and current value. Anything newly bought (within six months or a year - not sure of the US regs) may be subject to customs duty or possibly sales tax based on which state you are shipping them to.
Cheers,
Bev