I have a vintage Homelite T-10 tractor. Does anyone know what model number the tiller attachment that would go with this tractor?

Boy are you in luck. It takes a certain kind of nerd to be a big fan of vintage lawn tractors, and another kind of nerd to be a big fan of haunting advice forums. I'm both.

Check this out: http://www.simpletractors.com/Main/homelite.htm

That's the cross-reference page at the Simple Tractors website, dedicated to vintage Allis-Chalmers and Simplicity lawn and garden equipment. Your Homelite was made by one of them. Your T-10 takes the 36" tiller, and at least one Simplicity 36" tiller model was the Homelite model with no modifications, except for the paint color.

The Homelite model number for (one of) the 36" tiller models is: 1690039. That is ALSO the Simplicity model number, and if you expand your search to include Simplicity products you will be casting a much wider net.

You may have trouble finding a tiller to exactly fit your tractor, but that equipment was built to last, unlike modern products. You have a chance, but it won't be easy.

[edit]

Okay, that link, for some reason, was something I attached to something else yesterday. When I attached it this morning it was right, now it's just weird. I have fixed it for anyone else reading up on this kind of thing..

Sorry about the hassle, but I'm glad you were able to find the site.

Nice tractor, BTW. The Simplicity and A-C line from back then were rock solid, comparable to the toughest Deere equivalents. You can farm with them.

Good luck with it.

AWESOME! The link didnt work but I found the page you meant to paste in there! No worries on finding a hitch, I can fabricate anything i need to adapt! Thank you so much for the information!