There are 6 different followers that you can have to assist you with various quests through-out the game. Below are their names and where to find them!

Faendal: This chap can be found near the Wood Mill in Riverwood. He can also train you in archery, for a small fee, but I wouldnt worry about the cost as you have access to his gold so you can just take it straight back.

Goldir: Goto Hillgrund's Tomb and help him defeat a warlock and he'll be recruitable once he goes outside.

Jenassa: You'll find Jenassa in the Drunken Huntsman in Whiterun. This one costs 500g every time you hire her.

Lydia: You'll come across her as you complete the main storyline as she'll be your personal assistant but if you need her location for whatever reason its outside Dragonsreach.

Sven: You'll find Sven in the Giant Sleeping Inn.

Uthgerd the Unbroken: You'll find this charming "lady" in the Bannered Mare Tavern. She'll expect a fight before she'll work for you tho so come prepared!