Mac Fluidline is probably the best bet. Although, I think it's more important to make sure you invest in a great brush. 

I like the L'Oreal Carbon Black liquid E/L because it has a felt tip that gives precise lining.  And it lasts all day.  MAC fluidline is great too.

Gel/cream liner is a good way to go, but make sure you have a good brush! MAC Fluidline, Stila Smudgepots and Physicians Formula Gel Creamliners are some of my favorite liners, and the PF trio comes with its own fabulous brush.

Liquid is good too, but can be hard to use. Eyeliner marker/pens are easier but not as dramatic looking as liquid.

These are some great liner suggests, I would just add that if you want it to last all day, try using an eyelid primer before applying it. Urban Decay makes a great one and it can help almost any eye product last longer.

I like the Tarte Amazonian Clay Waterproof Liners. I have the color Bronze and it is co creaym and it really stays put. I think the proce is around $18 and the pot is really big. I have been putting it on with Tarte Double Ended Eyeliner Brush.

I have two favorite eyeliners and both will last until I take it off. One is Bobbi Brown Gel Eyeliner and the other is Clinique Cream Brush On Liner. I have oily eyelids and that's my test of a good liner. I've tried many eyeliners and find those two do the job.

I think Clinique's creme/gel liners are much more creamy than any other creme liner Ive tried including the Mac fluidlines. I know you wont be disapointed, they are cremey, pigmented, rich and dont dry out.