Birth certificate(recently issued), marriage certificate (recently issued), and educational diplomas (yes they want the actual diploma) as well as educational transcripts. Get them apostilled just prior to coming to Peru. To be safe get the original plus 1 or 2 copies of each since many places want to see these (or even keep them) and they are expensive to get from the US once you are in Peru.
If you have a US drivers license, get the international drivers permit just prior to departure (good for one year). You can get this at AAA. This will save you time and $.
If you are looking for work, bring signed letters from all previous employers verifying the dates of employment and basic description of the work that you performed. If the employer has an official looking stamp or seal that makes the letter look more legitimate.
The secretary of state's office in your home US state can apostille these documents for a fee. Check to see if they require them to be notarized prior to being apostilled.
Educational documents in Peru need further processing even after they have been apostilled.
If you have questions feel free to PM me. Good luck!!!