Where can I find a mower deck for a 42 in Weed Eater Tractor?

Try an online auction site, or contact some of the local mower shops, many shops have used parts at usually about half price of a new part.

Most of these off- brands are manufactured by either MTD or AYP. Poulan bought Weed Eater a while back and I know Poulan doesn't make there own stuff. Try asking on the Web who manufactures the product. You will need the Model & Serial Numbers to cross reference it . Good Luck

Still in all, you may be able to purchase a used deck.