There is now a cartography table for messing with maps but I seem to be able to use the crafting table for everything I've tested, the only difference is that scaling up a map only takes 1 paper instead of the 8 you need in the crafting table.
You did mean the in game maps for showing where you are? Or did you mean worlds?
Whether you hold it with one or both hands depends on whether or not you have something in your offhand/shield slot, it doesn't affect anything except how easy it is to see where you are, it's larger when held in both hands.
Is your map blank or already filled in partly or completely?
Do you have the little white marker that should show where you are?
You need to use the map, right click while holding it, to get it "started".
And if you're still in Creative mode it lets you keep the unused map and creates a new "started" map and puts it in another inventory slot which is easy to miss, especially if your hotbar is full and the new map ends up in your main inventory, viewable by clicking on the chest icon at the bottom of the Creative inventory screen.
I was confused for a while by that when I tested after seeing this thread but after figuring it out I promptly forgot about it and didn't think to mention it until now.
Maybe you weren't in Creative mode last time you used them?
That's sort of built into Creative mode, when you use a stack of blocks (or just one) they never run out, it's just not as obvious with something like a map.
(It really isn't obvious at all, when I tested it I ended up with an inventory full of maps because my hotbar was full and nothing at all seemed to happen when I "used" the map since the started maps went straight into my invisible inventory.)