Looking at engagement rings

Help ladies. So my boyfriend of two years had been dropping hints about wanting to marry me and propose to me. He asked me to think about what kind of ring I like and I'm not that type of girl who really daydreams about those things. I do like something nice but I never thought about this. I don't want a diamond ring, too expensive and don't like the business of diamond harvesting and advertising. But how should I start looking? Do I ask for his budget? etc.