Canon is the best for offering mic inputs in it's entry level cams. Canon MV890 or MV901 both have a mic input, and are very good for the money, and cost under £200.
Better are the Canon MVX450/460, but they are very hard to find.
or the new Canon MD101 which is now available; £200
http://www.amazon.co.uk/exec/obidos/...r-21/ref=nosim
The MD101 is effectively a replacement for the MV890/MV901; I haven't seen it reviewed or in action but I would expect it to be as good or better than the older models.