I've tried using ice cubes and I didn't like it. Especially when they're touching 'down there', to me it almost hurt.
but if you want something a little less extreme you could always get a glass or metal toy and that can feel cold to the touch or you can put it in cool water to make it whatever temperature you like.

I've stuck ice cubes up there and I actually kinda like it. Just remember, if you're using an ice dildo, to only use it for small amounts of time since ice can actually hurt you.

When I was much younger, well before ever purchasing any real sex toys, I would often take ice cubes from the freezer, rub the sharp edges until they became smooth, and put them into my butt. Sometimes several in one go.

I rather liked it, and I still do this once in a long while, but it gets uncomfortable pretty quickly. I like the idea of being able to put something completely inside of me without fear of losing it completely (as it simply melts).

I like it if my partner sucks on an ice cube for a little while and then goes down on me. I do not like it though if the ice cube is in her mouth and makes contact with my skin. Too cold

externally a light teasing is great!

I once had a guy put ice in his mouth while he was going down on me. Not only was it cold, it was uncomfortable. I prefer warm mouths, free of unnecessary obstructions.