fisheye lens troubles..

[boxcarbinny]

new here.. having a little dilemma...

I just got a fish eye lens for my Konica Minolta camera (it was my aunts camera, it's like 10 years old lol) anyway the fish eye is a vivitar and the lens is a Minolta but I read that if I had an adapter ring I'll be ok.. (i sure hope ill be okay, at least!!) Anyway they fish eye came with 2 and they don't fit the lens, sadly, they are 7/55mm and 7/49mm and my cameras lens is 28-80 0.38/1.3ft macro (just telling everyone know everything lol) does anyone have any idea what size adapter rings I should try getting? Any ideas would be great! Thank you!! =D And can I get them on ebay? is that an okay place to try? should i get one.. or a few.. hmm..

-Jenna