How do I find out where my large purchases are

Are you referring to the sales tax deduction?  Only you would know whether you had any major purchases. 

Federal>Deductions and Credits>Estimates and Other Taxes Paid> Sales Tax. 

Sales tax is an itemized deduction. “Major purchases” that you can enter for the sales tax deduction include:

Motor Vehicles (cars, trucks, motor homes, RV’s, sport utility vehicles and off-road vehicles

Aircraft or boats

Mobile homes

Manufactured housing

Building materials for major home improvements

You cannot deduct: furniture, jewelry, home electronics such as TV’s or computers

https://ttlc.intuit.com/questions/1901222-which-deduction-should-i-choose-sales-tax-or-income-tax

https://ttlc.intuit.com/questions/2566624-how-much-sales-tax-did-i-pay-last-year

https://ttlc.intuit.com/questions/3148443-how-do-you-define-major-purchase-or-major-item-for-the-sales-tax-deduction

https://ttlc.intuit.com/questions/1900791-how-do-i-find-my-local-sales-tax

https://ttlc.intuit.com/questions/2566624-how-much-sales-tax-did-i-pay-last-year

When TurboTax asks if you bought any major items while living in your state, you should answer Yes if you purchased:

• A motorized vehicle (car, truck, RV, motorcycle, etc.—sorry, no mopeds).
• An aircraft, boat, mobile home, or manufactured home, but only if you paid the general sales tax rate (otherwise it doesn't apply).
• Building materials for a major renovation or substantial addition to a home, if you paid the general sales tax rate yourself or your contractor was authorized to purchase these materials per your instructions or building contract.

Otherwise, answer No, even if the items you purchased were expensive.

This question is being asked for purposes of determining whether to take a deduction for sales taxes paid as you might be better off deducting sales taxes if you made large purchases during the year and your total sales tax payments exceed those for state income taxes. You can use either the actual sales taxes you paid or the IRS optional sales tax tables

The deduction for your sales tax payments is only available if you itemize your deductions. To determine this, add up all of your expenses that are eligible to be itemized, including your sales taxes. If the total amount is greater than the standard deduction amount for your filing status, then you should likely itemize on Schedule A and claim the sales tax deduction.

The standard deduction amounts for 2023 are:

• $27,700 – Married Filing Jointly or Qualifying Surviving Spouse (increase of $1,800)
• $20,800 – Head of Household (increase of $1,400)
• $13,850 – Single or Married Filing Separately (increase of $900)

Taxpayers who are 65 and Older or are Blind

For 2023, the additional standard deduction amounts for taxpayers who are 65 and older or blind are:

• $1,850 for Single or Head of Household (increase of $100)
• $1,500 for married taxpayers or Qualifying Surviving Spouse (increase of $100)

Click here for how to define a major purchase.

Click here for how to write off sales taxes.

Click here for Sales Tax Claculator.