Trying to get this for my Level 2 Divination Wizard. Can marketplace items PLEASE be directly linked from their dedicated pages? Items are easily found from the search bar but to actually purchase them requires jumping through hoops. Drives me nuts.

Alternatively, if I've got it wrong appreciate anyone pointing me to the right source book, thanks.

It's free. You don't need to buy it.

O.o

Detect thoughts isn’t showing as available for purchase because it is free content available to everyone in the free basic rules, no purchase necessary. 

The reason you cannot add it to your 2nd level Wizard is because it is a 2nd-level spell, and Wizards cannot learn 2nd-level spells until they reach 3rd level. Class levels are not at a 1:1 ration with spell levels as there are only 9 levels worth of spells (10 if you include Cantrips), but a Wiz can reach 20th level. Please see The Wizard Table, as well as the Spell Level section of the Basic Rules for more information: 

Spell Level

Every spell has a level from 0 to 9. A spell's level is a general indicator of how powerful it is, with the lowly (but still impressive) magic missile at 1st level and the earth-shaking wish at 9th. Cantrips -- simple but powerful spells that characters can cast almost by rote -- are level 0. The higher a spell's level, the higher level a spellcaster must be to use that spell.

Spell level and character level don't correspond directly. Typically, a character has to be at least 17th level, not 9th level, to cast a 9th-level spell.

Quote from IamSposta >>

Detect thoughts isn’t showing as available for purchase because it is free content available to everyone in the free basic rules, no purchase necessary. 

The reason you cannot add it to your 2nd level Wizard is because it is a 2nd-level spell, and Wizards cannot learn 2nd-level spells until they reach 3rd level. Class levels are not at a 1:1 ration with spell levels as there are only 9 levels worth of spells (10 if you include Cantrips), but a Wiz can reach 20th level. Please see The Wizard Table, as well as the Spell Level section of the Basic Rules for more information: 

Spell Level

Every spell has a level from 0 to 9. A spell's level is a general indicator of how powerful it is, with the lowly (but still impressive) magic missile at 1st level and the earth-shaking wish at 9th. Cantrips -- simple but powerful spells that characters can cast almost by rote -- are level 0. The higher a spell's level, the higher level a spellcaster must be to use that spell.

Spell level and character level don't correspond directly. Typically, a character has to be at least 17th level, not 9th level, to cast a 9th-level spell.

Ok many thanks!

Happy to help.