The Philanthropist Point Shop is located in the Silph Co in Saffron City. In particular, Inside you can obtain these items after talking to the NPC:
You can obtain PP in many various ways. Some include:
Altar blessing: You can get PP by donating to the Altar Blessing in Vermillion city. $1,000=1PP; 1 Credit = $1,500
Various blessings (World, Christmas, Drop, Halloween): Use these blessings every hour. You get 500 max, if there is more than 500 people on currently. If there is less than 500 people on, then you get the PP according to the number of people on (For example, if there's 430 people on, you get 430 PP.). These are located in the credit shop. The Enhanced World Blessing gives a max of 1500 pp, depending on the amount of people online.
Item Bomb- You can also get PP from setting off item bombs. You get 1200 PP as a base, plus x number of PP for the amount of people on. So if you have 700 people on it's 1200 PP (base) plus 700 people, resulting in 1900 PP. These are located in the credit shop.