First off, you are never going to find the right helmet unless you go somewhere that has a wide selection, and try a bunch of them on. People's heads and faces are all different shapes, and each helmet manufacturer fits differently. To find your correct size, and the right one for your head and face shape, you are going to have to try on a bunch of different brands. That'll help you decide which brand helmet fits your particular head.
I'm a Shoei guy, for example. I have tried two different Arai helmets, and neither of them worked out for me. They never "fit right".
Second thing to consider is what type of riding do you do?
When I rode every single day, rain or shine, on the freeway, in commuter traffic, for more an hour each way, I spent $1000 on a fantastic helmet. If I was gonna crash, it was going to be fast, in traffic, and with many things flying at my head.
Nowadays, I mostly run quick errands on my bike. I may do a couple hour leisurely ride on back roads once a month, or so. But mostly I am running down to the hardware store for something, doing some light shopping, or cruising around and sightseeing around town.
So I still have my hardcore full-face, high tech helmet, for the long rides. (Last year I rode from Seattle to San Francisco for my 30th high school reunion. Wore the "serious" helmet for that trip.)
But most days I wear my 3/4 helmet. Like this one. Integrated flip-down sun visor. Face shield flips up and exposes my face and mouth so I can talk to the cashier at the hardware store. It's more noisy than my full-face helmet, and can buffet pretty badly at freeway speeds, but it's great for around-town riding.
Any helmet less than $250 is as effective as wearing a KFC bucket on your head.
Anything over $750 is overkill unless you ride professionally, or do 20k miles in a year.
Buy your helmet too tight. They stretch after a month or so of wear, and you want this thing to last 5 years. If it makes you look like chipmunk-cheeks for a month, but keeps you safe for 5+ years, that's a completely reasonable tradeoff.
Feel free to look at Revzilla and send me links. Ask about helmets. I have Opinions. :-)