Here are my recommendations. Like someone else said, a good concealer can greatly help with the uner-eye circles/darkness, also, but a good eye cream is always a must.
Anyway, I use Shiseido Benefiance Anti-Wrinkle eye cream. I love it. I was noticing some very fine lines, and since I've been using this, they've greatly decreased. It also helps somewhat with my under-eye circles; however, I use Make Up For Ever Lift Concealer under my eyes and it's awesome. It conceals the darkness beautifully. It has a bit of irredescence in it that reflects light, thus diminishing the circles. You only need a tiny bit and it's very soft and doesn't settle into any little lines you might have. I use #1, but you might need a different color based on your skin tone. Sephora carries the Make Up Forever so you can try it out on your hand to check for the shade (or you can look at it online at their website) and I buy the Shiseido at Macy's.
Also, if the Shiseido doesn't work for you, I've recently begun using Cosmedicine SPF 20 day cream and Private Nurse night cream. I believe they have an eye cream also. I can't attest to that product because I haven't used it, but their other creams that I do use are fantastic. You might want to check them out. Also, the old standby, Estee Lauder Advanced Night Repair eye cream is another great product. I used that for years, but switched to the Shiseido because I felt my skin needed something different as I was starting to see those very fine lines. I think maybe it just stopped working as well since I used it for so long.
Good luck with your search!