Diamond Ring?

[Mei-chan]

I heard that I can get it from lighthalzen but when I went there, I can't find it in at the wedding npc.
Is there a specific spot or way to get it?

[-John-]

There's one in Morroc, go south, near the south warp. The npc called Jewel Seller. 

[Firemousey]

You can buy Diamond Rings in LH. You need to go into the "Department Store" first - its the building closest to the Warp Girl I believe. Once you go inside, go upstairs and you'll find an NPC that looks just like the Wedding NPC in the Prontera Church. You can buy the Rings from her but you can't get married in LH.

[Razer]

They can also be bought in westernmost prontera. There are 3 shops here - Hair dyer,Wedding supplies and 1 more.