I use the body shop's ultra smooth liquid concealer. its amazing. £7.50 for a 7ml tube but you dont need a lot so it'll last a while and it goes on kind of creamy a bit like a mousse foundation.
i'm a fan of stila's stick concealers and foundations. they don't clog my pores, they blend easily, and they actually match my skin. Sometimes I will layer them veeery lightly with bare essentials bisque or summer bisque.
right now I'm using benefit bo-ing for blemishes and lemon-aid for under the eye, (i have blueishness under my eyes and the yellowish primer covers it well)
I just purchased Laura Mercier's Secret Camaflouge and it definately lives up to the hype. I love that it comes with two different shades! I can blend them for different areas of my face AND I can use the lighter shade by itself as a highlight.
Laura mercier Secret Camoflauge is perfect for covering any spots/marks and stays put, and under my eyes, the BEST one I've found is Aveda inner light as it isn't drying like most under eye concealers, and boy have I tried plenty!!!
I use concealer by makeup artist Eve Pearl (this stuff is fantastic). It's my HG and I use it on everyone. My second HG is Kryolan's DermaColor. It's a paramedical concealer. More dense and you use very little.