35 mm adaptor
 

I want to attach my 35mm 300 mm and 75 mm canon lenses (made by Tamron) off my rebel xt to my Sony V1, Does anyone know which adaptor will work

You would need to use an adapter with an EOS mount. Furthermore, you'd need to be using manual lenses, since electronic lenses typically have closed apertures when not receiving a signal to open. Additionally, you probably want to stick with primes, since zoom lenses are typically not fast enough for video adaptation.

Unless that is a very fast 300mm lens, it will likely have trouble working with a 35mm adapter. Most adapters need quality fast lenses. Also, you can simulate the shallow DOF effect of a 300mm lens just by zooming your V1 in and keeping the iris open.