I love belts and have an entire drawer full. I usually buy mine at TJMaxx and try to wear the clothing that I want the belt for. I usually only buy real leather belts. I agree that sometimes, the men's section has a better selection!
For something a little different, a few of us have tried out the Hipsi belt that viva recommended a couple of weeks ago. I'm waiting for an exchange of a smaller size, but even the bigger size was plenty adjustable enough for me at my hips; I just wanted one belt that I can wear at my waist and at my hips (in leather belts, those are two completely different sizes).
I think the Hipsi just might be my perfect belt, because it doesn't feel like a belt! I don't feel it at all. It doesn't press into my hip bones, it doesn't adjust too tight or too loose, it doesn't stick out in the back when I sit. I don't feel the need to loosen it when I'm driving. I also think it's a GREAT choice for when you just want something decorative but don't necessarily need to hold up your pants, because it's barely there, if that makes sense! But it also does work for holding up pants/jeans. I have a few pairs that are too big or ride down, and this belt has taken care of that problem completely. I'm amazed! But... it's a stretchy belt, so it's not leather.