Both of the above options are a good shout as they'll give you a good overview of different types of delay.
I say this because there's no point getting an analogue delay, hating it and giving up, whereas all you needed was a good digital delay.....or vice versa.
Once you know what you like, you can look at more specific units .
My faves are the Boss DM-3, Akai Headrush E2, Line 6 DL-4 & Idiotbox Dimension X, but there are so many more!
Si