Q:

Is there a specific armor set fitting an archer?

I know i need light armor for my sneaking and movement, but what specific set and enchantments would fit best?

A:

The most generic, directly useful enchant for an archer is, obviously, the Fortify Archery effect.
Some unique armor includes:

Gauntlets of the Old Gods,
All varieties of the Shrouded Cowl, especially the Ancient,
Linwe's hood, which also add 15% damage to bows,
The Dragon Mask Krosis reinforce it to 20%.

After you got these, you still need to cover you feet and torso. These pieces cannot be enchanted with Forty Archery, but other things can be useful:

Muffle boots (you can find this, eg. on the shrouded armor),
Fortify Sneak boots (or hood) (Boots of the Old Good or Linwe's boots have it), 
Fortify Stamina on armor,
Fortify Light Armor,
You can also use some elemental resistance, depending on your Ring and Amulet or special abilities (resist fire if you are a vampire, for example)

You can of course posses different set of armor, depending on the circumstances. I always like to keep an Thieves Guild Armor on me for when I am over my carry limit, and a pair of gloves with a stabbing multiplier.

