You can reference the controls of the repeater in the ItemCreated event of the dropdown list using the items FindControl method.
I recall having some trouble with it being databound, from memory I bound the dropdown in the ItemCreated event also.
There is a great 16 Part article at 4guysfromrolla.com about datagrids, most of it would also apply to repeaters I beleive and is worth a read.
They say, best men are molded out of faults,
And, for the most, become much more the better
For being a little bad.