I want to learn the spell but I don't know where to get the tome from.
Telekinesis doesn't exist as a pre-placed book in the base game, though if you have either Dawnguard or Dragonborn, there will be a book in two dungeons added by the expansions, namely Redwater Den for Dawnguard, and Benkongerike for Dragonborn.
Beyond that, it is also possible to find a Telekinesis spell tome as loot from any boss chests (though, admittedly, the chance of finding a specific spell this way is slim), and because Telekinesis is listed as an Adept-level spell, you must be at least level 23 to boot.
Finally, perhaps the simplest way (and only guaranteed way if you don't have the DLC), is to buy the spell directly, from either Tolfdir at the mage's college or from Wylandriah, the court mage of Riften.
If neither of these spell vendors offer Telekinesis for sale, it means your alteration skill is too low, and must be at least 40 for them to offer it to you.
- Purchase from Tolfdir at the College of Winterhold.
- May be found in Labyrinthian.
- Found during the Vampire quest to fill the Bloodstone Chalice in a jail cell by an ash pile. DG (Redwater Den)
- Can rarely be found in the Master locked chest in the Thieves Guild.
- Found in Benkongerike Great Halls' first room, hidden beneath a pile of Lusty Argonian Maid books. DB
Straight from the wiki