lgn1 - 7:32 pm on Jun 26, 2012 (gmt 0)

Does anyone know if the manufacturer can legally stop me from selling their product that I bought at retail? Could I be sued for this?

No, It falls under the first sale doctrine, and exhaustion of rights. (At least in the USA and Canada).

But, rather than buying retail. Enter into a partnership (profit sharing) relationship with a retailer. Some of the merchandise will be diverted from the retail side to the online side. It is best done, if you have friends, family, relatives in the retail industry; rather than approaching any retailer blind.